1
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Mondal P, Saha SK, Roy P, Vasudeva N, Anshu A, Rajasekar GP, Pandey A. Plasmon Mediated Single Photon Emission from a Nanocrystal Ensemble. J Phys Chem Lett 2024; 15:7556-7565. [PMID: 39024059 DOI: 10.1021/acs.jpclett.4c00540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
Quantum photonic devices require robust sources of single photons to perform basic computational and communication protocols. Thus, developing scalable, integrable, and efficient quantum light sources has become crucial for the realization of quantum photonic devices. Single quantum dots are promising sources of quantum light due to their tunable emission wavelength. Here, we show the emergence of quantum-emitter-like antibunched emission behavior when multiple quantum dots are located in the vicinity of plasmonic particles. To evaluate the robustness of this phenomenon, we consider both monometallic and bimetallic particles. We find that the photoluminescence intensity of the plasmon coupled quantum dots fits well to a single sublinear power law exponent that is distinct from the behavior of CQD aggregates. Significantly, we find that plasmon coupling results in reduced flickering, thus enabling the realization of a more stable and reliable single photon source. Possible roles of emergent excitonic interactions in the coupled system are discussed.
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Affiliation(s)
- Pritha Mondal
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Subham Kumar Saha
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Parna Roy
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Navyashree Vasudeva
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Ashwini Anshu
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Guru Pratheep Rajasekar
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Anshu Pandey
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
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2
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Cichos F, Xia T, Yang H, Zijlstra P. The ever-expanding optics of single-molecules and nanoparticles. J Chem Phys 2024; 161:010401. [PMID: 38949895 DOI: 10.1063/5.0221680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2024] [Accepted: 06/10/2024] [Indexed: 07/03/2024] Open
Affiliation(s)
- F Cichos
- Peter Debye Institute for Soft Matter Physics, Leipzig University, Leipzig, Germany
| | - T Xia
- Institute for Immunology, School of Medicine, Tsinghua University, Beijing, China
| | - H Yang
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA
| | - P Zijlstra
- Department of Applied Physics and Science Education, Eindhoven University of Technology (TU/e), Eindhoven, The Netherlands
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3
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Scott JM, Dale SG, McBroom J, Gould T, Li Q. Size Isn't Everything: Geometric Tuning in Polycyclic Aromatic Hydrocarbons and Its Implications for Carbon Nanodots. J Phys Chem A 2024; 128:2003-2014. [PMID: 38470339 DOI: 10.1021/acs.jpca.3c07416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/13/2024]
Abstract
Recent developments in light-emitting carbon nanodots and molecular organic semiconductors have seen renewed interest in the properties of polycyclic aromatic hydrocarbons (PAHs) as a family. The networks of delocalized π electrons in sp2-hybridized carbon grant PAHs light-emissive properties right across the visible spectrum. However, the mechanistic understanding of their emission energy has been limited due to the ground state-focused methods of determination. This computational chemistry work, therefore, seeks to validate existing rules and elucidate new features and characteristics of PAHs that influence their emissions. Predictions based on (time-dependent) density functional theory account for the full 3-dimensional electronic structure of ground and excited states and reveal that twisting and near-degeneracies strongly influence emission spectra and may therefore be used to tune the color of PAHs and, hence, carbon nanodots. We particularly note that the influence of twisting goes beyond torsional destabilization of the ground-state and geometric relaxation of the excited state, with a third contribution associated with the electric transition dipole. Symmetries and peri-condensation may also have an effect, but this could not be statistically confirmed. In pursuing this goal, we demonstrate that with minimal changes to molecular size, the entire visible spectrum may be spanned by geometric modification alone; we have also provided a first estimate of emission energy for 35 molecules currently lacking published emission spectra as well as clear guidelines for when more sophisticated computational techniques are required to predict the properties of PAHs accurately.
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Affiliation(s)
- James M Scott
- Queensland Micro- and Nanotechnology Centre, Griffith University, Nathan, Queensland 4111, Australia
- School of Engineering and Built Environment, Griffith University, Nathan, Queensland 4111, Australia
| | - Stephen G Dale
- Queensland Micro- and Nanotechnology Centre, Griffith University, Nathan, Queensland 4111, Australia
- The Institute for Functional Intelligent Materials (I-FIM), National University of Singapore, 4 Science Drive 2, Singapore 117544, Singapore
| | - James McBroom
- School of Environment and Science, Griffith University, Nathan, Queensland 4111, Australia
| | - Tim Gould
- Queensland Micro- and Nanotechnology Centre, Griffith University, Nathan, Queensland 4111, Australia
- School of Environment and Science, Griffith University, Nathan, Queensland 4111, Australia
| | - Qin Li
- Queensland Micro- and Nanotechnology Centre, Griffith University, Nathan, Queensland 4111, Australia
- School of Engineering and Built Environment, Griffith University, Nathan, Queensland 4111, Australia
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4
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Zhang Y, Oberg CP, Hu Y, Xu H, Yan M, Scholes GD, Wang M. Molecular and Supramolecular Materials: From Light-Harvesting to Quantum Information Science and Technology. J Phys Chem Lett 2024:3294-3316. [PMID: 38497707 DOI: 10.1021/acs.jpclett.4c00264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
The past two decades have witnessed immense advances in quantum information technology (QIT), benefited by advances in physics, chemistry, biology, and materials science and engineering. It is intriguing to consider whether these diverse molecular and supramolecular structures and materials, partially inspired by quantum effects as observed in sophisticated biological systems such as light-harvesting complexes in photosynthesis and the magnetic compass of migratory birds, might play a role in future QIT. If so, how? Herein, we review materials and specify the relationship between structures and quantum properties, and we identify the challenges and limitations that have restricted the intersection of QIT and chemical materials. Examples are broken down into two categories: materials for quantum sensing where nonclassical function is observed on the molecular scale and systems where nonclassical phenomena are present due to intermolecular interactions. We discuss challenges for materials chemistry and make comparisons to related systems found in nature. We conclude that if chemical materials become relevant for QIT, they will enable quite new kinds of properties and functions.
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Affiliation(s)
- Yipeng Zhang
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, Guangdong 518172, P. R. China
| | - Catrina P Oberg
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Yue Hu
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Hongxue Xu
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, Guangdong 518172, P. R. China
| | - Mengwen Yan
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, Guangdong 518172, P. R. China
| | - Gregory D Scholes
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Mingfeng Wang
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, Guangdong 518172, P. R. China
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5
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Adhikari S, Smit R, Orrit M. Future Paths in Cryogenic Single-Molecule Fluorescence Spectroscopy. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2024; 128:3-18. [PMID: 38229590 PMCID: PMC10788914 DOI: 10.1021/acs.jpcc.3c06564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 11/23/2023] [Accepted: 11/28/2023] [Indexed: 01/18/2024]
Abstract
In the last three decades, cryogenic single-molecule fluorescence spectroscopy has provided average-free understanding of the photophysics and of fundamental interactions at molecular scales. Furthermore, they propose original pathways and applications in the treatment and storage of quantum information. The ultranarrow lifetime-limited zero-phonon line acts as an excellent sensor to local perturbations caused either by intrinsic dynamical degrees of freedom, or by external perturbations, such as those caused by electric fields, elastic and acoustic deformations, or light-induced dynamics. Single aromatic hydrocarbon molecules, being sensitive to nanoscale probing at nanometer scales, are potential miniaturized platforms for integrated quantum photonics. In this Perspective, we look back at some of the past advances in cryogenic optical microscopy and propose some perspectives for future development.
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Affiliation(s)
| | - Robert Smit
- Huygens−Kamerlingh
Onnes Laboratory, Leiden University, 2300 RA Leiden, The Netherlands
| | - Michel Orrit
- Huygens−Kamerlingh
Onnes Laboratory, Leiden University, 2300 RA Leiden, The Netherlands
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6
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Kumara BN, Shambhu R, Shim YB, Nirmal J, Prasad KS. Development of mucoadhesive Timolol loaded chitosan-nanocomposite to treat glaucoma. Int J Biol Macromol 2023; 253:126917. [PMID: 37716661 DOI: 10.1016/j.ijbiomac.2023.126917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Revised: 09/04/2023] [Accepted: 09/13/2023] [Indexed: 09/18/2023]
Abstract
Timolol Maleate is an aqueous soluble β-blocker antiglaucoma drug used to suppress intraocular pressure. Several commercially available ocular formulations are not effective in delivering to the target site due to their water-soluble property and low mucoadhesiveness. Hence, there is a requirement for a highly mucoadhesive drug-loaded nanocomposite to suppress intraocular pressure with enhanced bioavailability. Herein, we have prepared a mucoadhesive Timolol-loaded graphene quantum dot-chitosan-nanocomposite to treat glaucoma in response to lysozyme, secreted in the tear fluid. The as-prepared nanocomposite has been characterized through high resolution-transmission electron microscopic, X-ray photoelectron spectroscopic, X-ray diffraction, and Fourier transform infrared spectral studies. The nanocomposite showed 93.74 % encapsulation efficiency with a loading capacity of 7.73 %. Further, 89.26 %, 95.62 %, and 99.29 % of drug release were observed from the nanocomposite in the presence of 1, 1.5, and 2 mg/mL of lysozyme. The mucoadhesion property has been confirmed by the increment in the particle size, fluorescence spectral variations, and Fourier transform infrared spectroscopic studies in the presence of mucin nanoparticles of size 291 nm. Interestingly, mucoadhesion has been demonstrated by pointing to the quenching in the luminescence of mucin. Further, in vitro biocompatibility assay on human corneal epithelial cells showed ≥80 % cell viability. Hence, this study offers the utilization of naturally secreting enzymes for drug delivery applications instead of uncontrolled pH and temperature-triggered releases.
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Affiliation(s)
- B N Kumara
- Nanomaterial Research Laboratory [NMRL], Nano Division, Yenepoya Research Centre, Yenepoya [Deemed to be University], Deralakatte, Mangalore 575 018, India
| | - R Shambhu
- Department of Ophthalmology, Yenepoya Medical College, Yenepoya [Deemed to be University], Deralakatte, Mangalore 575 018, India
| | - Yoon-Bo Shim
- Department of Chemistry, Institute of BioPhysio Sensor Technology (IBST), Pusan National University, Busan 46241, South Korea
| | - Jayabalan Nirmal
- Translational Pharmaceutics Research Laboratory (TPRL), Department of Pharmacy, Birla Institute of Technology and Sciences (BITS), Pilani, Hyderabad Campus, Hyderabad, 500078, Telangana, India
| | - K Sudhakara Prasad
- Nanomaterial Research Laboratory [NMRL], Nano Division, Yenepoya Research Centre, Yenepoya [Deemed to be University], Deralakatte, Mangalore 575 018, India; Centre for Nutrition Studies, Yenepoya [Deemed to be University], Deralakatte, Mangalore 575 018, India.
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7
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Kulahava T, Belko N, Parkhats M, Bahdanava A, Lepeshkevich S, Chizhevsky V, Mogilevtsev D. Photostability and phototoxicity of graphene quantum dots interacting with red blood cells. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 2023; 248:112800. [PMID: 37857078 DOI: 10.1016/j.jphotobiol.2023.112800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 09/27/2023] [Accepted: 10/09/2023] [Indexed: 10/21/2023]
Abstract
Here we discuss fluorescent properties of graphene quantum dots (GQDs) interacting with the membranes of red blood cells. We report the results of spectroscopic, microscopic, and photon-counting measurements of the GQDs in different surroundings for uncovering specific features of the GQD fluorescence, and describe two observed phenomena important for implementation of the GQDs as fluorescent labels and agents for drug delivery. Firstly, the GQDs can suffer from photodegradation but also can be stabilized in the presence of antioxidants (reduced glutathione, N-acetylcysteine, or 1,4-hydroquinone). Secondly, GQDs can accumulate in red blood cell membranes without compromising the viability of the cells but also can induce hemolysis in the presence of visible light. We discuss mechanisms and regimes of the photodegradation, stabilization, interaction of the GQDs with red blood cell membranes, and hemolysis. Notably, photohemolysis for the case is dependent on the light dose and GQD concentration but not caused by the production of reactive oxygen species.
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Affiliation(s)
- Tatsiana Kulahava
- Institute for Nuclear Problems of the Belarusian State University, Bobruiskaya str. 11, Minsk 220006, Belarus
| | - Nikita Belko
- B.I. Stepanov Institute of Physics, NAS of Belarus, Nezavisimosty ave. 68, Minsk 220072, Belarus.
| | - Marina Parkhats
- B.I. Stepanov Institute of Physics, NAS of Belarus, Nezavisimosty ave. 68, Minsk 220072, Belarus
| | - Anastasiya Bahdanava
- Institute for Nuclear Problems of the Belarusian State University, Bobruiskaya str. 11, Minsk 220006, Belarus
| | - Sergei Lepeshkevich
- B.I. Stepanov Institute of Physics, NAS of Belarus, Nezavisimosty ave. 68, Minsk 220072, Belarus
| | - Vyacheslav Chizhevsky
- B.I. Stepanov Institute of Physics, NAS of Belarus, Nezavisimosty ave. 68, Minsk 220072, Belarus
| | - Dmitri Mogilevtsev
- B.I. Stepanov Institute of Physics, NAS of Belarus, Nezavisimosty ave. 68, Minsk 220072, Belarus.
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8
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Fu W, Yin J, Cao H, Zhou Z, Zhang J, Fu J, Warner JH, Wang C, Jia X, Greaves GN, Cheetham AK. Non-Blinking Luminescence from Charged Single Graphene Quantum Dots. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2304074. [PMID: 37395476 DOI: 10.1002/adma.202304074] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 06/24/2023] [Accepted: 06/26/2023] [Indexed: 07/04/2023]
Abstract
Photoluminescence blinking behavior from single quantum dots under steady illumination is an important but controversial topic. Its occurrence has impeded the use of single quantum dots in bioimaging. Different mechanisms have been proposed to account for it, although controversial, the most important of which is the non-radiative Auger recombination mechanism whereby photocharging of quantum dots can lead to the blinking phenomenon. Here, the singly charged trion, which maintains photon emission, including radiative recombination and non-radiative Auger recombination, leads to fluorescence non-blinking which is observed in photocharged single graphene quantum dots (GQDs). This phenomenon can be explained in terms of different energy levels in the GQDs, caused by various oxygen-containing functional groups in the single GQDs. The suppressed blinking is due to the filling of trap sites owing to a Coulomb blockade. These results provide a profound understanding of the special optical properties of GQDs, affording a reference for further in-depth research.
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Affiliation(s)
- Wei Fu
- Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Jiefu Yin
- Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Huaqiang Cao
- Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Zhongfu Zhou
- State Key Laboratory of Advanced Special Steel, Shanghai Key Laboratory of Advanced Ferrometallurgy, Shanghai University, Shanghai, 200072, China
| | - Junying Zhang
- School of Physics, Beihang University, Beijing, 100191, China
| | - Jingjing Fu
- School of Medicine, Tsinghua University, Beijing, 100084, China
| | - Jamie H Warner
- Department of Mechanical Engineering, The University of Texas at Austin, 204 East Dean Keeton Street, Austin, TX, 78712, USA
| | - Cheng Wang
- Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Xiaofang Jia
- School of Physics, Beihang University, Beijing, 100191, China
| | - G Neville Greaves
- Department of Physics, Aberystwyth University, Aberystwyth, SY23 3BZ, UK
- Department of Materials Science and Metallurgy, The University of Cambridge, Cambridge, CB3 0FS, UK
| | - Anthony K Cheetham
- Department of Materials Science and Metallurgy, The University of Cambridge, Cambridge, CB3 0FS, UK
- Materials Research Laboratory, University of California, Santa Barbara, CA, 93106, USA
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9
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Medina-Lopez D, Liu T, Osella S, Levy-Falk H, Rolland N, Elias C, Huber G, Ticku P, Rondin L, Jousselme B, Beljonne D, Lauret JS, Campidelli S. Interplay of structure and photophysics of individualized rod-shaped graphene quantum dots with up to 132 sp² carbon atoms. Nat Commun 2023; 14:4728. [PMID: 37550308 PMCID: PMC10406913 DOI: 10.1038/s41467-023-40376-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 07/24/2023] [Indexed: 08/09/2023] Open
Abstract
Nanographene materials are promising building blocks for the growing field of low-dimensional materials for optics, electronics and biophotonics applications. In particular, bottom-up synthesized 0D graphene quantum dots show great potential as single quantum emitters. To fully exploit their exciting properties, the graphene quantum dots must be of high purity; the key parameter for efficient purification being the solubility of the starting materials. Here, we report the synthesis of a family of highly soluble and easily processable rod-shaped graphene quantum dots with fluorescence quantum yields up to 94%. This is uncommon for a red emission. The high solubility is directly related to the design of the structure, allowing for an accurate description of the photophysical properties of the graphene quantum dots both in solution and at the single molecule level. These photophysical properties were fully predicted by quantum-chemical calculations.
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Affiliation(s)
- Daniel Medina-Lopez
- Université Paris-Saclay, CEA, CNRS, NIMBE, LICSEN, 91191, Gif-sur-Yvette, France
| | - Thomas Liu
- Université Paris-Saclay, CNRS, ENS Paris-Saclay, CentraleSupélec, LuMIn, 91400, Orsay, France
| | - Silvio Osella
- Chemical and Biological Systems Simulation Lab, Centre of New Technologies, University of Warsaw, Banacha 2C, 02-097, Warsaw, Poland
| | - Hugo Levy-Falk
- Université Paris-Saclay, CNRS, ENS Paris-Saclay, CentraleSupélec, LuMIn, 91400, Orsay, France
| | - Nicolas Rolland
- Laboratory for Chemistry of Novel Materials, University of Mons, 7000, Mons, Belgium
| | - Christine Elias
- Université Paris-Saclay, CNRS, ENS Paris-Saclay, CentraleSupélec, LuMIn, 91400, Orsay, France
| | - Gaspard Huber
- Université Paris-Saclay, CEA, CNRS, NIMBE, LSDRM, 91191, Gif-sur-Yvette, France
| | - Pranav Ticku
- Université Paris-Saclay, CNRS, ENS Paris-Saclay, CentraleSupélec, LuMIn, 91400, Orsay, France
| | - Loïc Rondin
- Université Paris-Saclay, CNRS, ENS Paris-Saclay, CentraleSupélec, LuMIn, 91400, Orsay, France
| | - Bruno Jousselme
- Université Paris-Saclay, CEA, CNRS, NIMBE, LICSEN, 91191, Gif-sur-Yvette, France
| | - David Beljonne
- Laboratory for Chemistry of Novel Materials, University of Mons, 7000, Mons, Belgium
| | - Jean-Sébastien Lauret
- Université Paris-Saclay, CNRS, ENS Paris-Saclay, CentraleSupélec, LuMIn, 91400, Orsay, France.
| | - Stephane Campidelli
- Université Paris-Saclay, CEA, CNRS, NIMBE, LICSEN, 91191, Gif-sur-Yvette, France.
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10
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Liang L, Shen X, Zhou M, Chen Y, Lu X, Zhang L, Wang W, Shen JW. Theoretical Evaluation of Potential Cytotoxicity of Graphene Quantum Dot to Adsorbed DNA. MATERIALS (BASEL, SWITZERLAND) 2022; 15:7435. [PMID: 36363026 PMCID: PMC9654448 DOI: 10.3390/ma15217435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Revised: 10/18/2022] [Accepted: 10/19/2022] [Indexed: 06/16/2023]
Abstract
As a zero-dimensional (0D) nanomaterial, graphene quantum dot (GQD) has a unique physical structure and electrochemical properties, which has been widely used in biomedical fields, such as bioimaging, biosensor, drug delivery, etc. Its biological safety and potential cytotoxicity to human and animal cells have become a growing concern in recent years. In particular, the potential DNA structure damage caused by GQD is of great importance but still obscure. In this study, molecular dynamics (MD) simulation was used to investigate the adsorption behavior and the structural changes of single-stranded (ssDNA) and double-stranded DNA (dsDNA) on the surfaces of GQDs with different sizes and oxidation. Our results showed that ssDNA can strongly adsorb and lay flat on the surface of GQDs and graphene oxide quantum dots (GOQDs), whereas dsDNA was preferentially oriented vertically on both surfaces. With the increase of GQDs size, more structural change of adsorbed ssDNA and dsDNA could be found, while the size effect of GOQD on the structure of ssDNA and dsDNA is not significant. These findings may help to improve the understanding of GQD biocompatibility and potential applications of GQD in the biomedical field.
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Affiliation(s)
- Lijun Liang
- Center for X-Mechanics, Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province, School of Aeronautics and Astronautics, Zhejiang University, Hangzhou 310027, China
- College of Automation, Hangzhou Dianzi University, Hangzhou 310018, China
| | - Xin Shen
- School of Pharmacy, Hangzhou Normal University, Hangzhou 311121, China
- Key Laboratory of Elemene Class Anti-Cancer Chinese Medicines, Engineering Laboratory of Development and Application of Traditional Chinese Medicines, Collaborative Innovation Center of Traditional Chinese Medicines of Zhejiang Province, Hangzhou Normal University, Hangzhou 311121, China
| | - Mengdi Zhou
- School of Pharmacy, Hangzhou Normal University, Hangzhou 311121, China
| | - Yijian Chen
- School of Pharmacy, Hangzhou Normal University, Hangzhou 311121, China
- Key Laboratory of Elemene Class Anti-Cancer Chinese Medicines, Engineering Laboratory of Development and Application of Traditional Chinese Medicines, Collaborative Innovation Center of Traditional Chinese Medicines of Zhejiang Province, Hangzhou Normal University, Hangzhou 311121, China
| | - Xudong Lu
- School of Pharmacy, Hangzhou Normal University, Hangzhou 311121, China
- Key Laboratory of Elemene Class Anti-Cancer Chinese Medicines, Engineering Laboratory of Development and Application of Traditional Chinese Medicines, Collaborative Innovation Center of Traditional Chinese Medicines of Zhejiang Province, Hangzhou Normal University, Hangzhou 311121, China
| | - Li Zhang
- Key Laboratory of Surface & Interface Science of Polymer Materials of Zhejiang Province, Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Wei Wang
- Department of Pharmacy, Hangzhou Third People’s Hospital, Affiliated Hangzhou Dermatology Hospital, Zhejiang University School of Medicine, West Lake Road 38, Hangzhou 310009, China
| | - Jia-Wei Shen
- School of Pharmacy, Hangzhou Normal University, Hangzhou 311121, China
- Key Laboratory of Elemene Class Anti-Cancer Chinese Medicines, Engineering Laboratory of Development and Application of Traditional Chinese Medicines, Collaborative Innovation Center of Traditional Chinese Medicines of Zhejiang Province, Hangzhou Normal University, Hangzhou 311121, China
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11
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de Oteyza DG, Frederiksen T. Carbon-based nanostructures as a versatile platform for tunable π-magnetism. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:443001. [PMID: 35977474 DOI: 10.1088/1361-648x/ac8a7f] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 08/17/2022] [Indexed: 06/15/2023]
Abstract
Emergence ofπ-magnetism in open-shell nanographenes has been theoretically predicted decades ago but their experimental characterization was elusive due to the strong chemical reactivity that makes their synthesis and stabilization difficult. In recent years, on-surface synthesis under vacuum conditions has provided unprecedented opportunities for atomically precise engineering of nanographenes, which in combination with scanning probe techniques have led to a substantial progress in our capabilities to realize localized electron spin states and to control electron spin interactions at the atomic scale. Here we review the essential concepts and the remarkable advances in the last few years, and outline the versatility of carbon-basedπ-magnetic materials as an interesting platform for applications in spintronics and quantum technologies.
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Affiliation(s)
- Dimas G de Oteyza
- Nanomaterials and Nanotechnology Research Center (CINN), CSIC-UNIOVI-PA, E-33940 El Entrego, Spain
- Donostia International Physics Center (DIPC)-UPV/EHU, E-20018 San Sebastián, Spain
| | - Thomas Frederiksen
- Donostia International Physics Center (DIPC)-UPV/EHU, E-20018 San Sebastián, Spain
- Ikerbasque, Basque Foundation for Science, E-48013 Bilbao, Spain
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12
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Novel chitosan - graphene quantum dots composite for therapeutic delivery and tracking through enzymatic stimuli response. Carbohydr Polym 2022; 289:119426. [DOI: 10.1016/j.carbpol.2022.119426] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/02/2022] [Accepted: 03/26/2022] [Indexed: 12/11/2022]
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13
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Vimalanathan K, Scott J, Pan X, Luo X, Rahpeima S, Sun Q, Zou J, Bansal N, Prabawati E, Zhang W, Darwish N, Andersson MR, Li Q, Raston CL. Continuous flow fabrication of green graphene oxide in aqueous hydrogen peroxide. NANOSCALE ADVANCES 2022; 4:3121-3130. [PMID: 36132816 PMCID: PMC9419056 DOI: 10.1039/d2na00310d] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Accepted: 05/18/2022] [Indexed: 06/16/2023]
Abstract
Highly processible graphene oxide (GO) has a diversity of applications as a material readily dispersed in aqueous media. However, methods for preparing such free-standing GO use hazardous and toxic reagents and generate significant waste streams. This is an impediment for uptake of GO in any application, for developing sustainable technologies and industries, and overcoming this remains a major challenge. We have developed a robust scalable continuous flow method for fabricating GO directly from graphite in 30% aqueous hydrogen peroxide which dramatically minimises the generation of waste. The process features the continuous flow thin film microfluidic vortex fluidic device (VFD), operating at specific conditions while irradiated sequentially by UV LED than a NIR pulsed laser. The resulting 'green' graphene oxide (gGO) has unique properties, possessing highly oxidized edges with large intact sp2 domains which gives rise to exceptional electrical and optical properties, including purple to deep blue emission of narrow full width at half maximum (<35 nm). Colloidally stable gGO exhibits cytotoxicity owing to the oxidised surface groups while solid-state films of gGO are biocompatible. The continuous flow method of generating gGO also provides unprecedented control of the level of oxidation and its location in the exfoliated graphene sheets by harnessing the high shear topological fluid flows in the liquid, and varying the wavelength, power and pulse frequency of the light source.
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Affiliation(s)
- Kasturi Vimalanathan
- Flinders Institute for Nanoscale Science and Technology, College of Science and Engineering, Flinders University Adelaide SA 5001 Australia
| | - James Scott
- Environmental Engineering and Queensland Micro and Nanotechnology Centre, Griffith University Brisbane QLD 4111 Australia
| | - Xun Pan
- Flinders Institute for Nanoscale Science and Technology, College of Science and Engineering, Flinders University Adelaide SA 5001 Australia
| | - Xuan Luo
- Flinders Institute for Nanoscale Science and Technology, College of Science and Engineering, Flinders University Adelaide SA 5001 Australia
- Centre for Marine Bioproducts Development, College of Medicine and Public Health, Flinders University Adelaide SA 5042 Australia
| | - Soraya Rahpeima
- Flinders Institute for Nanoscale Science and Technology, College of Science and Engineering, Flinders University Adelaide SA 5001 Australia
- School of Molecular and Life Sciences, Curtin Institute for Functional Molecule and Interfaces, Curtin University Bentley Western Australia 6102 Australia
| | - Qiang Sun
- Centre for Microscopy and Microanalysis, The University of Queensland Brisbane QLD 4072 Australia
- Materials Engineering, The University of Queensland St Lucia QLD 4072 Australia
| | - Jin Zou
- Centre for Microscopy and Microanalysis, The University of Queensland Brisbane QLD 4072 Australia
- Materials Engineering, The University of Queensland St Lucia QLD 4072 Australia
| | - Nidhi Bansal
- School of Agriculture and Food Sciences, The University of Queensland St Lucia QLD Australia
| | - Elisabeth Prabawati
- School of Agriculture and Food Sciences, The University of Queensland St Lucia QLD Australia
| | - Wei Zhang
- Centre for Marine Bioproducts Development, College of Medicine and Public Health, Flinders University Adelaide SA 5042 Australia
| | - Nadim Darwish
- School of Molecular and Life Sciences, Curtin Institute for Functional Molecule and Interfaces, Curtin University Bentley Western Australia 6102 Australia
| | - Mats R Andersson
- Flinders Institute for Nanoscale Science and Technology, College of Science and Engineering, Flinders University Adelaide SA 5001 Australia
| | - Qin Li
- Environmental Engineering and Queensland Micro and Nanotechnology Centre, Griffith University Brisbane QLD 4111 Australia
| | - Colin L Raston
- Flinders Institute for Nanoscale Science and Technology, College of Science and Engineering, Flinders University Adelaide SA 5001 Australia
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14
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Liu Z, Fu S, Liu X, Narita A, Samorì P, Bonn M, Wang HI. Small Size, Big Impact: Recent Progress in Bottom-Up Synthesized Nanographenes for Optoelectronic and Energy Applications. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2106055. [PMID: 35218329 PMCID: PMC9259728 DOI: 10.1002/advs.202106055] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 01/31/2022] [Indexed: 05/20/2023]
Abstract
Bottom-up synthesized graphene nanostructures, including 0D graphene quantum dots and 1D graphene nanoribbons, have recently emerged as promising candidates for efficient, green optoelectronic, and energy storage applications. The versatility in their molecular structures offers a large and novel library of nanographenes with excellent and adjustable optical, electronic, and catalytic properties. In this minireview, recent progress on the fundamental understanding of the properties of different graphene nanostructures, and their state-of-the-art applications in optoelectronics and energy storage are summarized. The properties of pristine nanographenes, including high emissivity and intriguing blinking effect in graphene quantum dots, superior charge transport properties in graphene nanoribbons, and edge-specific electrochemistry in various graphene nanostructures, are highlighted. Furthermore, it is shown that emerging nanographene-2D material-based van der Waals heterostructures provide an exciting opportunity for efficient green optoelectronics with tunable characteristics. Finally, challenges and opportunities of the field are highlighted by offering guidelines for future combined efforts in the synthesis, assembly, spectroscopic, and electrical studies as well as (nano)fabrication to boost the progress toward advanced device applications.
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Affiliation(s)
- Zhaoyang Liu
- University of StrasbourgCNRSISIS UMR 70068 allée Gaspard MongeStrasbourg67000France
| | - Shuai Fu
- Max Planck Institute for Polymer ResearchAckermannweg 10Mainz55128Germany
| | - Xiaomin Liu
- Max Planck Institute for Polymer ResearchAckermannweg 10Mainz55128Germany
| | - Akimitsu Narita
- Max Planck Institute for Polymer ResearchAckermannweg 10Mainz55128Germany
- Organic and Carbon Nanomaterials UnitOkinawa Institute of Science and Technology Graduate University1919‐1 Tancha, Onna‐sonKunigamiOkinawa904‐0495Japan
| | - Paolo Samorì
- University of StrasbourgCNRSISIS UMR 70068 allée Gaspard MongeStrasbourg67000France
| | - Mischa Bonn
- Max Planck Institute for Polymer ResearchAckermannweg 10Mainz55128Germany
| | - Hai I. Wang
- Max Planck Institute for Polymer ResearchAckermannweg 10Mainz55128Germany
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15
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Khan SN, Weight BM, Gifford BJ, Tretiak S, Bishop A. Impact of Graphene Quantum Dot Edge Morphologies on Their Optical Properties. J Phys Chem Lett 2022; 13:5801-5807. [PMID: 35726899 DOI: 10.1021/acs.jpclett.2c01036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The optoelectronic properties of functionalized graphene quantum dots (GQDs) have been explored by simulating electronic structure of three different shapes of GQDs containing exclusively zigzag or armchair edges in both pristine and functionalized forms. Absorption spectra and transition densities for the low-lying excited states are evaluated by using time-dependent density functional theory and compared for different functionalization species. The functionalization position dictates the optical properties of square GQDs, where isomers with CH2 in the intermediate positions (excluding corner and center positions) have higher electronic transition energies and exciton delocalization than other isomers. Rhombic GQDs with all armchair edges exhibit high steric flexibility, and their complete passivation results in the largest structural deformation from planarity and strongest red-shifts. A steady red-shift in the absorption energy is observed following the order F, CH3, Cl, and Br substitutions. This suggests that the steric effects due to large van der Waals radii overcome electronegative effects.
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Affiliation(s)
- Shahriar N Khan
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849-5312, United States
- Theoretical Division, Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Braden M Weight
- Theoretical Division, Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
- Department of Physics, University of Rochester, Rochester, New York 14627, United States
| | - Brendan J Gifford
- Theoretical Division, Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Sergei Tretiak
- Theoretical Division, Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Alan Bishop
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
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16
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Gu Y, Vega‐Mayoral V, Garcia‐Orrit S, Schollmeyer D, Narita A, Cabanillas‐González J, Qiu Z, Müllen K. Cove‐Edged Hexa‐
peri
‐hexabenzo‐bis‐
peri
‐octacene: Molecular Conformations and Amplified Spontaneous Emission. Angew Chem Int Ed Engl 2022; 61:e202201088. [PMID: 35192234 PMCID: PMC9311809 DOI: 10.1002/anie.202201088] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Indexed: 12/14/2022]
Affiliation(s)
- Yanwei Gu
- Synthetic Chemistry Max Planck Institute for Polymer Research Ackermannweg 10 55128 Mainz Germany
| | - Victor Vega‐Mayoral
- Madrid Institute for Advanced Studies IMDEA Nanociencia c/Faraday 9, Campus de Cantoblanco 28049 Madrid Spain
| | - Saül Garcia‐Orrit
- Madrid Institute for Advanced Studies IMDEA Nanociencia c/Faraday 9, Campus de Cantoblanco 28049 Madrid Spain
| | - Dieter Schollmeyer
- Department of chemistry Johannes Gutenberg University Mainz Duesbergweg 10–14 55128 Mainz Germany
| | - Akimitsu Narita
- Synthetic Chemistry Max Planck Institute for Polymer Research Ackermannweg 10 55128 Mainz Germany
| | - Juan Cabanillas‐González
- Madrid Institute for Advanced Studies IMDEA Nanociencia c/Faraday 9, Campus de Cantoblanco 28049 Madrid Spain
| | - Zijie Qiu
- Synthetic Chemistry Max Planck Institute for Polymer Research Ackermannweg 10 55128 Mainz Germany
| | - Klaus Müllen
- Synthetic Chemistry Max Planck Institute for Polymer Research Ackermannweg 10 55128 Mainz Germany
- Institute for Physical Chemistry Johannes Gutenberg University Mainz Duesbergweg 10–14 55128 Mainz Germany
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17
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Cai KB, Huang HY, Hsieh ML, Chen PW, Chiang SE, Chang SH, Shen JL, Liu WR, Yuan CT. Two-Dimensional Self-Assembly of Boric Acid-Functionalized Graphene Quantum Dots: Tunable and Superior Optical Properties for Efficient Eco-Friendly Luminescent Solar Concentrators. ACS NANO 2022; 16:3994-4003. [PMID: 35234037 DOI: 10.1021/acsnano.1c09582] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Carbon-based nanomaterials hold promise for eco-friendly alternatives to heavy-metal-containing quantum dots (QDs) in optoelectronic applications. Here, boric acid-functionalized graphene quantum dots (B-GQDs) were prepared using bottom-up molecular fusion based on nitrated pyrenes and boric acid. Such B-GQDs with crystalline graphitic structures and hydrogen-bonding functionalities would be suitable model systems for unraveling the photoluminescence (PL) mechanism, while serving as versatile building blocks for supramolecular self-assembly. Unlike conventional GQDs with multiple emissive states, the B-GQDs exhibited excitation-wavelength-independent, vibronic-coupled excitonic emission. Interestingly, their PL spectra can be tuned without largely sacrificing the quantum yield (QY) due to two-dimensional self-assembly. In addition, such B-GQDs in a polystyrene matrix possessed an ultrahigh QY (∼90%) and large exciton binding energy (∼300 meV). Benefiting from broadband absorption, ultrahigh QY, and long-wavelength emission, efficient laminated luminescent solar concentrators (100 × 100 × 6.3 mm3) were fabricated, yielding a high power conversion efficiency (1.4%).
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Affiliation(s)
- Kun-Bin Cai
- Department of Physics, Chung Yuan Christian University, Taoyuan 320314, Taiwan
| | - Hsiu-Ying Huang
- Department of Physics, Chung Yuan Christian University, Taoyuan 320314, Taiwan
| | - Meng-Lin Hsieh
- Department of Chemical Engineering, Chung Yuan Christian University, Taoyuan 320314, Taiwan
| | - Po-Wen Chen
- Physics Division, Institute of Nuclear Energy Research, Taoyuan 325207, Taiwan
| | - Shou-En Chiang
- Department of Physics, Chung Yuan Christian University, Taoyuan 320314, Taiwan
| | - Sheng Hsiung Chang
- Department of Physics, Chung Yuan Christian University, Taoyuan 320314, Taiwan
| | - Ji-Lin Shen
- Department of Physics, Chung Yuan Christian University, Taoyuan 320314, Taiwan
| | - Wei-Ren Liu
- Department of Chemical Engineering, Chung Yuan Christian University, Taoyuan 320314, Taiwan
- R&D Center for Membrane Technology, Chung Yuan Christian University, Taoyuan 320314, Taiwan
| | - Chi-Tsu Yuan
- Department of Physics, Chung Yuan Christian University, Taoyuan 320314, Taiwan
- R&D Center for Membrane Technology, Chung Yuan Christian University, Taoyuan 320314, Taiwan
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18
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Liu T, Carles B, Elias C, Tonnelé C, Medina-Lopez D, Narita A, Chassagneux Y, Voisin C, Beljonne D, Campidelli S, Rondin L, Lauret JS. Vibronic fingerprints in the luminescence of graphene quantum dots at cryogenic temperature. J Chem Phys 2022; 156:104302. [DOI: 10.1063/5.0083282] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Atomically precise graphene quantum dots synthesized by bottom-up chemistry are promising versatile single emitters with potential applications for quantum photonic technologies. Toward a better understanding and control of graphene quantum dot (GQD) optical properties, we report on single-molecule spectroscopy at cryogenic temperature. We investigate the effect of temperature on the GQDs’ spectral linewidth and vibronic replica, which we interpret building on density functional theory calculations. Finally, we highlight that the vibronic signatures are specific to the GQD geometry and can be used as a fingerprint for identification purposes.
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Affiliation(s)
- Thomas Liu
- Université Paris-Saclay, ENS Paris-Saclay, CentraleSupélec, CNRS, LuMIn, Orsay, France
| | - Baptiste Carles
- Université Paris-Saclay, ENS Paris-Saclay, CentraleSupélec, CNRS, LuMIn, Orsay, France
| | - Christine Elias
- Université Paris-Saclay, ENS Paris-Saclay, CentraleSupélec, CNRS, LuMIn, Orsay, France
| | | | - Daniel Medina-Lopez
- Université Paris-Saclay, CEA, CNRS, NIMBE, LICSEN, 91191 Gif-sur-Yvette, France
| | - Akimitsu Narita
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Yannick Chassagneux
- LPENS, PSL, CNRS, Université de Paris, Sorbonne Université, 75005 Paris, France
| | - Christophe Voisin
- LPENS, PSL, CNRS, Université de Paris, Sorbonne Université, 75005 Paris, France
| | | | - Stéphane Campidelli
- Université Paris-Saclay, CEA, CNRS, NIMBE, LICSEN, 91191 Gif-sur-Yvette, France
| | - Loïc Rondin
- Université Paris-Saclay, ENS Paris-Saclay, CentraleSupélec, CNRS, LuMIn, Orsay, France
| | - Jean-Sébastien Lauret
- Université Paris-Saclay, ENS Paris-Saclay, CentraleSupélec, CNRS, LuMIn, Orsay, France
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19
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Liu T, Tonnelé C, Zhao S, Rondin L, Elias C, Medina-Lopez D, Okuno H, Narita A, Chassagneux Y, Voisin C, Campidelli S, Beljonne D, Lauret JS. Vibronic effect and influence of aggregation on the photophysics of graphene quantum dots. NANOSCALE 2022; 14:3826-3833. [PMID: 35194627 DOI: 10.1039/d1nr08279e] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Graphene quantum dots, atomically precise nanopieces of graphene, are promising nano-objects with potential applications in various domains such as photovoltaics, quantum light emitters and bio-imaging. Despite their interesting prospects, precise reports on their photophysical properties remain scarce. Here, we report on a study of the photophysics of C96H24(C12H25) graphene quantum dots. A combination of optical studies down to the single molecule level with advanced molecular modelling demonstrates the importance of coupling to vibrations in the emission process. Optical fingerprints for H-like aggregates are identified. Our combined experimental-theoretical investigations provide a comprehensive description of the light absorption and emission properties of nanographenes, which not only represents an essential step towards precise control of sample production but also paves the way for new exciting physics focused on twisted graphenoids.
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Affiliation(s)
- Thomas Liu
- Université Paris-Saclay, ENS Paris-Saclay, CentraleSupélec, CNRS, LuMIn, Orsay, France.
| | | | - Shen Zhao
- Université Paris-Saclay, ENS Paris-Saclay, CentraleSupélec, CNRS, LuMIn, Orsay, France.
| | - Loïc Rondin
- Université Paris-Saclay, ENS Paris-Saclay, CentraleSupélec, CNRS, LuMIn, Orsay, France.
| | - Christine Elias
- Université Paris-Saclay, ENS Paris-Saclay, CentraleSupélec, CNRS, LuMIn, Orsay, France.
| | - Daniel Medina-Lopez
- Université Paris-Saclay, CEA, CNRS, NIMBE, LICSEN, 91191, Gif-sur-Yvette, France
| | - Hanako Okuno
- University Grenoble Alpes, CEA INAC-MEM, F-38000 Grenoble, France
| | - Akimitsu Narita
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Yannick Chassagneux
- LPENS, PSL, CNRS, Université de Paris, Sorbonne Université, 75005 Paris, France
| | - Christophe Voisin
- LPENS, PSL, CNRS, Université de Paris, Sorbonne Université, 75005 Paris, France
| | - Stéphane Campidelli
- Université Paris-Saclay, CEA, CNRS, NIMBE, LICSEN, 91191, Gif-sur-Yvette, France
| | | | - Jean-Sébastien Lauret
- Université Paris-Saclay, ENS Paris-Saclay, CentraleSupélec, CNRS, LuMIn, Orsay, France.
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20
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Gu Y, Vega‐Mayoral V, Garcia‐Orrit S, Schollmeyer D, Narita A, Cabanillas‐González J, Qiu Z, Müllen K. Cove‐Edged Hexa‐
peri
‐hexabenzo‐bis‐
peri
‐octacene: Molecular Conformations and Amplified Spontaneous Emission. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202201088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Yanwei Gu
- Synthetic Chemistry Max Planck Institute for Polymer Research Ackermannweg 10 55128 Mainz Germany
| | - Victor Vega‐Mayoral
- Madrid Institute for Advanced Studies IMDEA Nanociencia c/Faraday 9, Campus de Cantoblanco 28049 Madrid Spain
| | - Saül Garcia‐Orrit
- Madrid Institute for Advanced Studies IMDEA Nanociencia c/Faraday 9, Campus de Cantoblanco 28049 Madrid Spain
| | - Dieter Schollmeyer
- Department of chemistry Johannes Gutenberg University Mainz Duesbergweg 10–14 55128 Mainz Germany
| | - Akimitsu Narita
- Synthetic Chemistry Max Planck Institute for Polymer Research Ackermannweg 10 55128 Mainz Germany
| | - Juan Cabanillas‐González
- Madrid Institute for Advanced Studies IMDEA Nanociencia c/Faraday 9, Campus de Cantoblanco 28049 Madrid Spain
| | - Zijie Qiu
- Synthetic Chemistry Max Planck Institute for Polymer Research Ackermannweg 10 55128 Mainz Germany
| | - Klaus Müllen
- Synthetic Chemistry Max Planck Institute for Polymer Research Ackermannweg 10 55128 Mainz Germany
- Institute for Physical Chemistry Johannes Gutenberg University Mainz Duesbergweg 10–14 55128 Mainz Germany
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21
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Kishida H, Mikkelsen MH. Ultrafast Lifetime and Bright Emission from Graphene Quantum Dots Using Plasmonic Nanogap Cavities. NANO LETTERS 2022; 22:904-910. [PMID: 35044773 DOI: 10.1021/acs.nanolett.1c03419] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Graphene quantum dots (GQDs) are quasi-zero-dimensional, carbon-based luminescent nanomaterials that possess desirable physical properties, such as high photostability, low cytotoxicity, good biocompatibility, and excellent water solubility; however, their long radiative lifetimes significantly limit their use in, e.g., light emitting devices where a fast spontaneous emission rate is essential. Despite a few reports on GQD fluorescence enhancements using metal nanostructures, studies of enhanced spontaneous emission rate remain outstanding. Here, we report fast and bright luminescence by coupling gap plasmon modes to nanoparticle emitters. Through precise control over the nanoparticle's local density of states (LDOS), we achieved a 220-fold increase in the PL intensity. The shortest radiative lifetime obtained was below 8.0 ps and limited by the instrument response, which is over 288-fold shorter than the lifetime of uncoupled GQDs. These findings may benefit the future development of rapid displays and open the possibility of constructing high-frequency classical or quantum telecommunication systems.
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Affiliation(s)
- Hiroyuki Kishida
- Department of Electrical and Computer Engineering, Duke University, Durham, North Carolina 27708, United States
| | - Maiken H Mikkelsen
- Department of Electrical and Computer Engineering, Duke University, Durham, North Carolina 27708, United States
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22
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Alfieri A, Anantharaman SB, Zhang H, Jariwala D. Nanomaterials for Quantum Information Science and Engineering. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022:e2109621. [PMID: 35139247 DOI: 10.1002/adma.202109621] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 02/04/2022] [Indexed: 06/14/2023]
Abstract
Quantum information science and engineering (QISE)-which entails the use of quantum mechanical states for information processing, communications, and sensing-and the area of nanoscience and nanotechnology have dominated condensed matter physics and materials science research in the 21st century. Solid-state devices for QISE have, to this point, predominantly been designed with bulk materials as their constituents. This review considers how nanomaterials (i.e., materials with intrinsic quantum confinement) may offer inherent advantages over conventional materials for QISE. The materials challenges for specific types of qubits, along with how emerging nanomaterials may overcome these challenges, are identified. Challenges for and progress toward nanomaterials-based quantum devices are condidered. The overall aim of the review is to help close the gap between the nanotechnology and quantum information communities and inspire research that will lead to next-generation quantum devices for scalable and practical quantum applications.
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Affiliation(s)
- Adam Alfieri
- Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Surendra B Anantharaman
- Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Huiqin Zhang
- Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Deep Jariwala
- Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, PA, 19104, USA
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23
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Drummer MC, Singh V, Gupta N, Gesiorski JL, Weerasooriya RB, Glusac KD. Photophysics of nanographenes: from polycyclic aromatic hydrocarbons to graphene nanoribbons. PHOTOSYNTHESIS RESEARCH 2022; 151:163-184. [PMID: 33963981 DOI: 10.1007/s11120-021-00838-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Accepted: 04/22/2021] [Indexed: 06/12/2023]
Abstract
Graphene quantum dots (GQDs) and nanoribbons (GNRs) are classes of nanographene molecules that exhibit highly tunable photophysical properties. There have been great strides in recent years to advance our understanding of nanographene photophysics and develop their use in light-harvesting systems, such as artificial photosynthesis. Here, we review the latest studies of GQDs and GNRs which have shed new light onto their photophysical underpinnings through computational and advanced spectroscopic techniques. We discuss how the size, symmetry, and shape of nanographenes influence their molecular orbital structures and, consequentially, their spectroscopic signatures. The scope of this review is to comprehensively lay out the general photophysics of nanographenes starting with benzene and building up to larger polycyclic aromatic hydrocarbons, GQDs, and GNRs. We also explore a collection of publications from recent years that build upon the current understanding of nanographene photophysics and their potential application in light-driven processes from display, lasing, and sensing technology to photocatalytic water splitting.
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Affiliation(s)
- Matthew C Drummer
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, IL, 60607, USA
- Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 Cass Avenue, Lemont, IL, 60439, USA
| | - Varun Singh
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, IL, 60607, USA
- Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 Cass Avenue, Lemont, IL, 60439, USA
| | - Nikita Gupta
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, IL, 60607, USA
- Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 Cass Avenue, Lemont, IL, 60439, USA
| | - Jonathan L Gesiorski
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, IL, 60607, USA
- Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 Cass Avenue, Lemont, IL, 60439, USA
| | - Ravindra B Weerasooriya
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, IL, 60607, USA
- Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 Cass Avenue, Lemont, IL, 60439, USA
| | - Ksenija D Glusac
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, IL, 60607, USA.
- Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 Cass Avenue, Lemont, IL, 60439, USA.
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24
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Paternò GM, Chen Q, Muñoz-Mármol R, Guizzardi M, Bonal V, Kabe R, Barker AJ, Boj PG, Chatterjee S, Ie Y, Villalvilla JM, Quintana JA, Scotognella F, Müllen K, Díaz-García MA, Narita A, Lanzani G. Excited states engineering enables efficient near-infrared lasing in nanographenes. MATERIALS HORIZONS 2022; 9:393-402. [PMID: 34605501 DOI: 10.1039/d1mh00846c] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The spectral overlap between stimulated emission (SE) and absorption from dark states (i.e. charges and triplets) especially in the near-infrared (NIR), represents one of the most effective gain loss channels in organic semiconductors. Recently, bottom-up synthesis of atomically precise graphene nanostructures, or nanographenes (NGs), has opened a new route for the development of environmentally and chemically stable materials with optical gain properties. However, also in this case, the interplay between gain and absorption losses has hindered the attainment of efficient lasing action in the NIR. Here, we demonstrate that the introduction of two fluoranthene imide groups to the NG core leads to a more red-shifted emission than the precursor NG molecule (685 vs. 615 nm) and also with a larger Stokes shift (45 nm vs. 2 nm, 1026 cm-1vs. 53 cm-1, respectively). Photophysical results indicate that, besides the minimisation of ground state absorption losses, such substitution permits to suppress the detrimental excited state absorption in the NIR, which likely arises from a dark state with charge-transfer character and triplets. This has enabled NIR lasing (720 nm) from all-solution processed distributed feedback devices with one order of magnitude lower thresholds than those of previously reported NIR-emitting NGs. This study represents an advance in the field of NGs and, in general, organic semiconductor photonics, towards the development of cheap and stable NIR lasers.
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Affiliation(s)
- Giuseppe M Paternò
- Center for Nano Science and Technology, Istituto Italiano di Tecnologia (IIT), Via Pascoli 10, 20133, Milano, Italy.
| | - Qiang Chen
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany.
| | - Rafael Muñoz-Mármol
- Departamento de Física Aplicada and Instituto Universitario de Materiales de Alicante, Universidad de Alicante, 03080 Alicante, Spain.
| | - Michele Guizzardi
- Physics Department, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milano, Italy
| | - Víctor Bonal
- Departamento de Física Aplicada and Instituto Universitario de Materiales de Alicante, Universidad de Alicante, 03080 Alicante, Spain.
| | - Ryota Kabe
- Organic Optoelectronics Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan
| | - Alexander J Barker
- Center for Nano Science and Technology, Istituto Italiano di Tecnologia (IIT), Via Pascoli 10, 20133, Milano, Italy.
| | - Pedro G Boj
- Departamento de Óptica, Farmacología y Anatomía and Instituto Universitario de Materiales de Alicante, Universidad de Alicante, 03080 Alicante, Spain
| | - Shreyam Chatterjee
- The Institute of Scientific and Industrial Research (SANKEN), Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan
| | - Yutaka Ie
- The Institute of Scientific and Industrial Research (SANKEN), Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan
| | - José M Villalvilla
- Departamento de Física Aplicada and Instituto Universitario de Materiales de Alicante, Universidad de Alicante, 03080 Alicante, Spain.
| | - José A Quintana
- Departamento de Óptica, Farmacología y Anatomía and Instituto Universitario de Materiales de Alicante, Universidad de Alicante, 03080 Alicante, Spain
| | - Francesco Scotognella
- Physics Department, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milano, Italy
| | - Klaus Müllen
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany.
- Institute of Physical Chemistry, Johannes Gutenberg University Mainz, Duesbergweg 10-14, 55128 Mainz, Germany
| | - María A Díaz-García
- Departamento de Física Aplicada and Instituto Universitario de Materiales de Alicante, Universidad de Alicante, 03080 Alicante, Spain.
| | - Akimitsu Narita
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany.
- Organic and Carbon Nanomaterials Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan.
| | - Guglielmo Lanzani
- Center for Nano Science and Technology, Istituto Italiano di Tecnologia (IIT), Via Pascoli 10, 20133, Milano, Italy.
- Physics Department, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milano, Italy
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Shahriar SMS, Nafiujjaman M, An JM, Revuri V, Nurunnabi M, Han DW, Lee YK. Graphene: A Promising Theranostic Agent. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1351:149-176. [DOI: 10.1007/978-981-16-4923-3_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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26
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Dorontić S, Jovanović S, Bonasera A. Shedding Light on Graphene Quantum Dots: Key Synthetic Strategies, Characterization Tools, and Cutting-Edge Applications. MATERIALS 2021; 14:ma14206153. [PMID: 34683745 PMCID: PMC8539078 DOI: 10.3390/ma14206153] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 10/07/2021] [Accepted: 10/14/2021] [Indexed: 01/09/2023]
Abstract
During the last 20 years, the scientific community has shown growing interest towards carbonaceous nanomaterials due to their appealing mechanical, thermal, and optical features, depending on the specific nanoforms. Among these, graphene quantum dots (GQDs) recently emerged as one of the most promising nanomaterials due to their outstanding electrical properties, chemical stability, and intense and tunable photoluminescence, as it is witnessed by a booming number of reported applications, ranging from the biological field to the photovoltaic market. To date, a plethora of synthetic protocols have been investigated to modulate the portfolio of features that GQDs possess and to facilitate the use of these materials for target applications. Considering the number of publications and the rapid evolution of this flourishing field of research, this review aims at providing a broad overview of the most widely established synthetic protocols and offering a detailed review of some specific applications that are attracting researchers’ interest.
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Affiliation(s)
- Slađana Dorontić
- “Vinča” Institute of Nuclear Sciences—National Institute of the Republic of Serbia, University of Belgrade, P.O. Box 522, 11000 Belgrade, Serbia;
| | - Svetlana Jovanović
- “Vinča” Institute of Nuclear Sciences—National Institute of the Republic of Serbia, University of Belgrade, P.O. Box 522, 11000 Belgrade, Serbia;
- Correspondence: (S.J.); (A.B.)
| | - Aurelio Bonasera
- Palermo Research Unit, Department of Physics and Chemistry—Emilio Segrè, University of Palermo, 90128 Palermo, Italy
- Correspondence: (S.J.); (A.B.)
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Wang Y, Zhao XJ, Wei RJ, Liang GJ, Wang K, Tan YZ, Yang Y. Dynamic variation of excitonic coupling in excited bilayer graphene quantum dots. CHINESE J CHEM PHYS 2021. [DOI: 10.1063/1674-0068/cjcp2109169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Yu Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Xin-jing Zhao
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Rong-Jing Wei
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Gui-jie Liang
- Hubei Key Laboratory of Low Dimensional Optoelectronic Materials and Devices, Hubei University of Arts and Science, Xiangyang 441053, China
| | - Kang Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Yuan-zhi Tan
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Ye Yang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
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Anantharaman SB, Jo K, Jariwala D. Exciton-Photonics: From Fundamental Science to Applications. ACS NANO 2021; 15:12628-12654. [PMID: 34310122 DOI: 10.1021/acsnano.1c02204] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Semiconductors in all dimensionalities ranging from 0D quantum dots and molecules to 3D bulk crystals support bound electron-hole pair quasiparticles termed excitons. Over the past two decades, the emergence of a variety of low-dimensional semiconductors that support excitons combined with advances in nano-optics and photonics has burgeoned an advanced area of research that focuses on engineering, imaging, and modulating the coupling between excitons and photons, resulting in the formation of hybrid quasiparticles termed exciton-polaritons. This advanced area has the potential to bring about a paradigm shift in quantum optics, as well as classical optoelectronic devices. Here, we present a review on the coupling of light in excitonic semiconductors and previous investigations of the optical properties of these hybrid quasiparticles via both far-field and near-field imaging and spectroscopy techniques. Special emphasis is given to recent advances with critical evaluation of the bottlenecks that plague various materials toward practical device implementations including quantum light sources. Our review highlights a growing need for excitonic material development together with optical engineering and imaging techniques to harness the utility of excitons and their host materials for a variety of applications.
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Affiliation(s)
- Surendra B Anantharaman
- Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Kiyoung Jo
- Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Deep Jariwala
- Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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29
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Haines P, Reger D, Träg J, Strauss V, Lungerich D, Zahn D, Jux N, Guldi DM. On the photophysics of nanographenes - investigation of functionalized hexa- peri-hexabenzocoronenes as model systems. NANOSCALE 2021; 13:801-809. [PMID: 33410836 DOI: 10.1039/d0nr06802k] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
In this study, we report on hexa-peri-hexabenzocoronenes (HBCs) as representative models for nanographenes. To this end, we synthesized a family of functionalized HBCs and investigated the impact of the substituents on the π-extended systems of the HBCs. DFT and TD-DFT calculations suggested a charge transfer character, which intensified as the electron density withdrawing effects of the substituents (-M-effect) increased. Unambiguous corroboration of the charge transfer character in the case of NO2-substituents was realized via steady-state absorption and fluorescence experiments, which focused on the dependencies on the solvent polarity and temperature featuring. Going beyond HBCs with NO2-substituents, time-correlated single photon counting, and femtosecond and nanosecond transient absorption spectroscopy unveiled long-lived singlet and triplet excited states. As a complement, we performed electrochemical and spectroelectrochemical measurements. These measurements were carried out to shed light onto the nature of the functionalized HBCs as electron acceptors and/or donors, on the one hand, and their corresponding spectroscopic signatures, on the other hand. All of the aforementioned information enabled intermolecular charge separation assays with, for example, suitable electron acceptors by steady-state and time-resolved spectroscopy.
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Affiliation(s)
- Philipp Haines
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM) Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058 Erlangen, Germany
| | - David Reger
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM) Friedrich-Alexander-Universität Erlangen-Nürnberg, Nikolaus-Fiebiger-Straße 10, 91058 Erlangen, Germany
| | - Johannes Träg
- Department of Chemistry and Pharmacy & Computer Chemistry Center (CCC) Friedrich-Alexander-Universität Erlangen-Nürnberg, Nägelsbachstraße 25, 91052 Erlangen, Germany
| | - Volker Strauss
- Max Planck Institut für Kolloid- und Grenzflächenforschung, Am Mühlenberg 1, 14476 Potsdam, Germany.
| | - Dominik Lungerich
- Center for Nanomedicine Institute for Basic Science (IBS), 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea and Graduate Program of Nano Biomedical Engineering (NanoBME) Advanced Science Institute, Yonsei University, Seoul 03722, Republic of Korea
| | - Dirk Zahn
- Department of Chemistry and Pharmacy & Computer Chemistry Center (CCC) Friedrich-Alexander-Universität Erlangen-Nürnberg, Nägelsbachstraße 25, 91052 Erlangen, Germany
| | - Norbert Jux
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM) Friedrich-Alexander-Universität Erlangen-Nürnberg, Nikolaus-Fiebiger-Straße 10, 91058 Erlangen, Germany
| | - Dirk M Guldi
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM) Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058 Erlangen, Germany
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30
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Telychko M, Li G, Mutombo P, Soler-Polo D, Peng X, Su J, Song S, Koh MJ, Edmonds M, Jelínek P, Wu J, Lu J. Ultrahigh-yield on-surface synthesis and assembly of circumcoronene into a chiral electronic Kagome-honeycomb lattice. SCIENCE ADVANCES 2021; 7:7/3/eabf0269. [PMID: 33523911 PMCID: PMC7810380 DOI: 10.1126/sciadv.abf0269] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 11/20/2020] [Indexed: 05/16/2023]
Abstract
On-surface synthesis has revealed remarkable potential in the fabrication of atomically precise nanographenes. However, surface-assisted synthesis often involves multiple-step cascade reactions with competing pathways, leading to a limited yield of target nanographene products. Here, we devise a strategy for the ultrahigh-yield synthesis of circumcoronene molecules on Cu(111) via surface-assisted intramolecular dehydrogenation of the rationally designed precursor, followed by methyl radical-radical coupling and aromatization. An elegant electrostatic interaction between circumcoronenes and metallic surface drives their self-organization into an extended superlattice, as revealed by bond-resolved scanning probe microscopy measurements. Density functional theory and tight-binding calculations reveal that unique hexagonal zigzag topology of circumcoronenes, along with their periodic electrostatic landscape, confines two-dimensional electron gas in Cu(111) into a chiral electronic Kagome-honeycomb lattice with two emergent electronic flat bands. Our findings open up a new route for the high-yield fabrication of elusive nanographenes with zigzag topologies and their superlattices with possible nontrivial electronic properties.
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Affiliation(s)
- Mykola Telychko
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Guangwu Li
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Pingo Mutombo
- Institute of Physics, The Czech Academy of Sciences, 162 00 Prague, Czech Republic
- Department of Petrochemistry and Refining, University of Kinshasa, Kinshasa, Democratic Republic of Congo
| | - Diego Soler-Polo
- Universidad Autónoma de Madrid, Campus Cantoblanco, Madrid, Spain
| | - Xinnan Peng
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Jie Su
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Shaotang Song
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Ming Joo Koh
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Mark Edmonds
- School of Physics and Astronomy, Monash University, Clayton, Victoria, Australia
| | - Pavel Jelínek
- Institute of Physics, The Czech Academy of Sciences, 162 00 Prague, Czech Republic.
- Regional Centre of Advanced Technologies and Materials, Palacký University, 78371 Olomouc, Czech Republic
| | - Jishan Wu
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore.
| | - Jiong Lu
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore.
- Centre for Advanced 2D Materials (CA2DM), National University of Singapore, 6 Science Drive 2, Singapore 117546, Singapore
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31
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Xu X, Chen Q, Narita A. Synthesis and Characterization of Dibenzo[<i>hi,st</i>]ovalene as a Highly Fluorescent Polycyclic Aromatic Hydrocarbon and Its π-Extension to Circumpyrene. J SYN ORG CHEM JPN 2020. [DOI: 10.5059/yukigoseikyokaishi.78.1094] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Xiushang Xu
- Organic and Carbon Nanomaterials Unit, Okinawa Institute of Science and Technology Graduate University
| | - Qiang Chen
- Max Planck Institute for Polymer Research
| | - Akimitsu Narita
- Organic and Carbon Nanomaterials Unit, Okinawa Institute of Science and Technology Graduate University
- Max Planck Institute for Polymer Research
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32
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Ghosh S, Oleksiievets N, Enderlein J, Chizhik AI. Emission States Variation of Single Graphene Quantum Dots. J Phys Chem Lett 2020; 11:7356-7362. [PMID: 32790308 DOI: 10.1021/acs.jpclett.0c02008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Graphene quantum dots (GQDs) are nanoparticles that consist of a nanometer-sized core of graphene with diverse chemical groups on its boundary. Due to their advantageous properties, they are considered to be a promising material for optoelectronics, bioimaging, or photovoltaics. Despite considerable efforts that have been focused on unraveling the mechanism of their photoluminescence, many fundamental details are still unclear. Here, we report on a single-particle multimodal study that provides new insight into the photoluminescence properties of emission centers of GQDs in various local chemical environments. In particular, we show that the properties that are associated with emission centers of GQDs are significantly more sensitive to the structure of the particle itself than to a nonuniform local chemical environment. A better understanding of the dependence of GQDs' emission states on the complex local chemical environment is an important step toward finding new ways of controlling the optical properties of GQDs and of optimizing their use in various applications.
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Affiliation(s)
- Subhabrata Ghosh
- Third Institute of Physics - Biophysics, University of Göttingen, 37077 Göttingen, Germany
| | - Nazar Oleksiievets
- Third Institute of Physics - Biophysics, University of Göttingen, 37077 Göttingen, Germany
| | - Jörg Enderlein
- Third Institute of Physics - Biophysics, University of Göttingen, 37077 Göttingen, Germany
- Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), University of Göttingen, 37077 Göttingen, Germany
| | - Alexey I Chizhik
- Third Institute of Physics - Biophysics, University of Göttingen, 37077 Göttingen, Germany
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33
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Riccardi E, Massabeau S, Valmorra F, Messelot S, Rosticher M, Tignon J, Watanabe K, Taniguchi T, Delbecq M, Dhillon S, Ferreira R, Balibar S, Kontos T, Mangeney J. Ultrasensitive Photoresponse of Graphene Quantum Dots in the Coulomb Blockade Regime to THz Radiation. NANO LETTERS 2020; 20:5408-5414. [PMID: 32470310 DOI: 10.1021/acs.nanolett.0c01800] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Graphene quantum dots (GQDs) have recently attracted considerable attention, with appealing properties for terahertz (THz) technology. This includes the demonstration of large thermal bolometric effects in GQDs when illuminated by THz radiation. However, the interaction of THz photons with GQDs in the Coulomb blockade regime, i.e., single electron transport regime, remains unexplored. Here, we demonstrate the ultrasensitive photoresponse to THz radiation (from <0.1 to 10 THz) of a hBN-encapsulated GQD in the Coulomb blockade regime at low temperature (170 mK). We show that THz radiation of ∼10 pW provides a photocurrent response in the nanoampere range, resulting from a renormalization of the chemical potential of the GQD of ∼0.15 meV. We attribute this photoresponse to an interfacial photogating effect. Furthermore, our analysis reveals the absence of thermal effects, opening new directions in the study of coherent quantum effects at THz frequencies in GQDs.
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Affiliation(s)
- Elisa Riccardi
- Laboratoire de Physique de l'Ecole Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, F-75005 Paris, France
| | - Sylvain Massabeau
- Laboratoire de Physique de l'Ecole Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, F-75005 Paris, France
| | - Federico Valmorra
- Laboratoire de Physique de l'Ecole Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, F-75005 Paris, France
| | - Simon Messelot
- Laboratoire de Physique de l'Ecole Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, F-75005 Paris, France
| | - Michael Rosticher
- Laboratoire de Physique de l'Ecole Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, F-75005 Paris, France
| | - Jérôme Tignon
- Laboratoire de Physique de l'Ecole Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, F-75005 Paris, France
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, Tsukuba, Ibaraki 305-0047, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba, Ibaraki 305-0047, Japan
| | - Matthieu Delbecq
- Laboratoire de Physique de l'Ecole Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, F-75005 Paris, France
| | - Sukhdeep Dhillon
- Laboratoire de Physique de l'Ecole Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, F-75005 Paris, France
| | - Robson Ferreira
- Laboratoire de Physique de l'Ecole Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, F-75005 Paris, France
| | - Sébastien Balibar
- Laboratoire de Physique de l'Ecole Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, F-75005 Paris, France
| | - Takis Kontos
- Laboratoire de Physique de l'Ecole Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, F-75005 Paris, France
| | - Juliette Mangeney
- Laboratoire de Physique de l'Ecole Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, F-75005 Paris, France
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34
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Tan T, Jiang X, Wang C, Yao B, Zhang H. 2D Material Optoelectronics for Information Functional Device Applications: Status and Challenges. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2020; 7:2000058. [PMID: 32537415 PMCID: PMC7284198 DOI: 10.1002/advs.202000058] [Citation(s) in RCA: 104] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 02/20/2020] [Accepted: 02/21/2020] [Indexed: 05/19/2023]
Abstract
Graphene and the following derivative 2D materials have been demonstrated to exhibit rich distinct optoelectronic properties, such as broadband optical response, strong and tunable light-mater interactions, and fast relaxations in the flexible nanoscale. Combining with optical platforms like fibers, waveguides, grating, and resonators, these materials has spurred a variety of active and passive applications recently. Herein, the optical and electrical properties of graphene, transition metal dichalcogenides, black phosphorus, MXene, and their derivative van der Waals heterostructures are comprehensively reviewed, followed by the design and fabrication of these 2D material-based optical structures in implementation. Next, distinct devices, ranging from lasers to light emitters, frequency convertors, modulators, detectors, plasmonic generators, and sensors, are introduced. Finally, the state-of-art investigation progress of 2D material-based optoelectronics offers a promising way to realize new conceptual and high-performance applications for information science and nanotechnology. The outlook on the development trends and important research directions are also put forward.
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Affiliation(s)
- Teng Tan
- Key Laboratory of Optical Fiber Sensing and Communications (Education Ministry of China)School of Information and Communication EngineeringUniversity of Electronic Science and Technology of ChinaChengdu611731China
| | - Xiantao Jiang
- Shenzhen Key Laboratory of Micro‐Nano Photonic Information TechnologyGuangdong Laboratory of Artificial Intelligence and Digital Economy (SZ)International Collaboration Laboratory of 2D Materials for Optoelectronic Science and TechnologyCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen518060China
| | - Cong Wang
- Shenzhen Key Laboratory of Micro‐Nano Photonic Information TechnologyGuangdong Laboratory of Artificial Intelligence and Digital Economy (SZ)International Collaboration Laboratory of 2D Materials for Optoelectronic Science and TechnologyCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen518060China
| | - Baicheng Yao
- Key Laboratory of Optical Fiber Sensing and Communications (Education Ministry of China)School of Information and Communication EngineeringUniversity of Electronic Science and Technology of ChinaChengdu611731China
| | - Han Zhang
- Shenzhen Key Laboratory of Micro‐Nano Photonic Information TechnologyGuangdong Laboratory of Artificial Intelligence and Digital Economy (SZ)International Collaboration Laboratory of 2D Materials for Optoelectronic Science and TechnologyCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen518060China
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35
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Ma C, Xiao Z, Puretzky AA, Wang H, Mohsin A, Huang J, Liang L, Luo Y, Lawrie BJ, Gu G, Lu W, Hong K, Bernholc J, Li AP. Engineering Edge States of Graphene Nanoribbons for Narrow-Band Photoluminescence. ACS NANO 2020; 14:5090-5098. [PMID: 32283017 DOI: 10.1021/acsnano.0c01737] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Solid-state narrow-band light emitters are on-demand for quantum optoelectronics. Current approaches based on defect engineering in low-dimensional materials usually introduce a broad range of emission centers. Here, we report narrow-band light emission from covalent heterostructures fused to the edges of graphene nanoribbons (GNRs) by controllable on-surface reactions from molecular precursors. Two types of heterojunction (HJ) states are realized by sequentially synthesizing GNRs and graphene nanodots (GNDs) and then coupling them together. HJs between armchair GNDs and armchair edges of the GNR are coherent and give rise to narrow-band photoluminescence. In contrast, HJs between the armchair GNDs and the zigzag ends of GNRs are defective and give rise to nonradiative states near the Fermi level. At low temperatures, sharp photoluminescence emissions with peak energy range from 2.03 to 2.08 eV and line widths of 2-5 meV are observed. The radiative HJ states are uniform, and the optical transition energy is controlled by the band gaps of GNRs and GNDs. As these HJs can be synthesized in a large quantity with atomic precision, this finding highlights a route to programmable and deterministic creation of quantum light emitters.
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Affiliation(s)
- Chuanxu Ma
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, United States
- Hefei National Research Center for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Zhongcan Xiao
- Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Alexander A Puretzky
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Hao Wang
- Department of Electrical Engineering and Computer Science, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Ali Mohsin
- Department of Electrical Engineering and Computer Science, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Jingsong Huang
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Computational Sciences and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Liangbo Liang
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Yingdong Luo
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Benjamin J Lawrie
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Gong Gu
- Department of Electrical Engineering and Computer Science, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Wenchang Lu
- Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, United States
- Computational Sciences and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Kunlun Hong
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Jerzy Bernholc
- Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, United States
- Computational Sciences and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - An-Ping Li
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, United States
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36
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Tadyszak K, Musiał A, Ostrowski A, Wychowaniec JK. Unraveling Origins of EPR Spectrum in Graphene Oxide Quantum Dots. NANOMATERIALS (BASEL, SWITZERLAND) 2020; 10:E798. [PMID: 32326319 PMCID: PMC7221827 DOI: 10.3390/nano10040798] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 03/12/2020] [Accepted: 04/17/2020] [Indexed: 01/17/2023]
Abstract
Carbon nanostructures are utilized in a plethora of applications ranging from biomedicine to electronics. Particularly interesting are carbon nanostructured quantum dots that can be simultaneously used for bimodal therapies with both targeting and imaging capabilities. Here, magnetic and optical properties of graphene oxide quantum dots (GOQDs) prepared by the top-down technique from graphene oxide and obtained using the Hummers' method were studied. Graphene oxide was ultra-sonicated, boiled in HNO3, ultra-centrifuged, and finally filtrated, reaching a mean flake size of ~30 nm with quantum dot properties. Flake size distributions were obtained from scanning electron microscopy (SEM) images after consecutive preparation steps. Energy-dispersive X-ray (EDX) confirmed that GOQDs were still oxidized after the fabrication procedure. Magnetic and photoluminescence measurements performed on the obtained GOQDs revealed their paramagnetic behavior and broad range optical photoluminescence around 500 nm, with magnetic moments of 2.41 µB. Finally, electron paramagnetic resonance (EPR) was used to separate the unforeseen contributions and typically not taken into account metal contaminations, and radicals from carbon defects. This study contributes to a better understanding of magnetic properties of carbon nanostructures, which could in the future be used for the design of multimodal imaging agents.
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Affiliation(s)
- Krzysztof Tadyszak
- Institute of Molecular Physics, Polish Academy of Sciences, ul. Smoluchowskiego 17, 60-179 Poznań, Poland
| | - Andrzej Musiał
- Institute of Molecular Physics, Polish Academy of Sciences, ul. Smoluchowskiego 17, 60-179 Poznań, Poland
| | - Adam Ostrowski
- Institute of Molecular Physics, Polish Academy of Sciences, ul. Smoluchowskiego 17, 60-179 Poznań, Poland
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37
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Rodt S, Reitzenstein S, Heindel T. Deterministically fabricated solid-state quantum-light sources. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:153003. [PMID: 31791035 DOI: 10.1088/1361-648x/ab5e15] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The controlled generation of non-classical states of light is a challenging task at the heart of quantum optics. Aside from the mere spirit of science, the related research is strongly driven by applications in photonic quantum technologies, including the fields of quantum communication, quantum computation, and quantum metrology. In this context, the realization of integrated solid-state-based quantum-light sources is of particular interest, due to the prospects for scalability and device integration. This topical review focuses on solid-state quantum-light sources which are fabricated in a deterministic fashion. In this framework we cover quantum emitters represented by semiconductor quantum dots, colour centres in diamond, and defect-/strain-centres in two-dimensional materials. First, we introduce the topic of quantum-light sources and non-classical light generation for applications in photonic quantum technologies, motivating the need for the development of scalable device technologies to push the field towards real-world applications. In the second part, we summarize material systems hosting quantum emitters in the solid-state. The third part reviews deterministic fabrication techniques and comparatively discusses their advantages and disadvantages. The techniques are classified in bottom-up approaches, exploiting the site-controlled positioning of the quantum emitters themselves, and top-down approaches, allowing for the precise alignment of photonic microstructures to pre-selected quantum emitters. Special emphasis is put on the progress achieved in the development of in situ techniques, which significantly pushed the performance of quantum-light sources towards applications. Additionally, we discuss hybrid approaches, exploiting pick-and-place techniques or wafer-bonding. The fourth part presents state-of-the-art quantum-dot quantum-light sources based on the fabrication techniques presented in the previous sections, which feature engineered functionality and enhanced photon collection efficiency. The article closes by highlighting recent applications of deterministic solid-state-based quantum-light sources in the fields of quantum communication, quantum computing, and quantum metrology, and by discussing future perspectives in the field of solid-state quantum-light sources.
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Affiliation(s)
- Sven Rodt
- Institute of Solid-State Physics, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
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38
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Starukhin AN, Nelson DK, Eurov DA, Kurdyukov DA, Golubev VG. Manifestation of fluorophore segmental motion in carbon dots in steady-state fluorescence experiments. Phys Chem Chem Phys 2020; 22:8401-8408. [DOI: 10.1039/d0cp00056f] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Perrin plot of carbon dots in aqueous glycerol solutions of different viscosity at T = 298 K.
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39
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Chen Q, Schollmeyer D, Müllen K, Narita A. Synthesis of Circumpyrene by Alkyne Benzannulation of Brominated Dibenzo[ hi, st]ovalene. J Am Chem Soc 2019; 141:19994-19999. [PMID: 31816238 DOI: 10.1021/jacs.9b10957] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A transition-metal catalyzed alkyne benzannulation allowed an unprecedented synthesis of circumpyrene, starting from 3,11-dibromo-6,14-dimesityldibenzo[hi,st]ovalene (DBOV). The circumpyrene was characterized by a combination of NMR, mass spectrometry, and single-crystal X-ray diffraction analysis, revealing its multizigzag-edged structure. Two newly introduced C═C bonds in circumpyrene strongly perturbed the electronic structures of DBOV, as evidenced by increased optical and electrochemical energy gaps. This is in good agreement with an increased number of Clar's sextets as well as a decreased number of π-electrons in the conjugation pathway of circumpyrene, according to anisotropy of the induced current density (ACID) calculations. The present approach opens a new avenue to multizigzag-edged nanographenes and offers insights into their (opto)electronic properties.
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Affiliation(s)
- Qiang Chen
- Max Planck Institute for Polymer Research , Ackermannweg 10 , 55128 , Mainz , Germany
| | - Dieter Schollmeyer
- Institut für Organische Chemie , Johannes Gutenberg-Universität Mainz , Duesbergweg 10-14 , 55099 Mainz , Germany
| | - Klaus Müllen
- Max Planck Institute for Polymer Research , Ackermannweg 10 , 55128 , Mainz , Germany.,Institute of Physical Chemistry , Johannes Gutenberg-Universität Mainz , Duesbergweg 10-14 , 55128 Mainz , Germany
| | - Akimitsu Narita
- Max Planck Institute for Polymer Research , Ackermannweg 10 , 55128 , Mainz , Germany.,Organic and Carbon Nanomaterials Unit , Okinawa Institute of Science and Technology Graduate University , 1919-1 Tancha, Onna-son, Kunigami , Okinawa 904-0495 , Japan
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40
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Lombardi F, Lodi A, Ma J, Liu J, Slota M, Narita A, Myers WK, Müllen K, Feng X, Bogani L. Quantum units from the topological engineering of molecular graphenoids. Science 2019; 366:1107-1110. [DOI: 10.1126/science.aay7203] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 10/30/2019] [Indexed: 12/20/2022]
Abstract
Robustly coherent spin centers that can be integrated into devices are a key ingredient of quantum technologies. Vacancies in semiconductors are excellent candidates, and theory predicts that defects in conjugated carbon materials should also display long coherence times. However, the quantum performance of carbon nanostructures has remained stunted by an inability to alter the sp2-carbon lattice with atomic precision. Here, we demonstrate that topological tailoring leads to superior quantum performance in molecular graphene nanostructures. We unravel the decoherence mechanisms, quantify nuclear and environmental effects, and observe spin-coherence times that outclass most nanomaterials. These results validate long-standing assumptions on the coherent behavior of topological defects in graphene and open up the possibility of introducing controlled quantum-coherent centers in the upcoming generation of carbon-based optoelectronic, electronic, and bioactive systems.
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Affiliation(s)
- Federico Lombardi
- Department of Materials, University of Oxford, 16 Parks Road, OX1 3PH Oxford, UK
| | - Alessandro Lodi
- Department of Materials, University of Oxford, 16 Parks Road, OX1 3PH Oxford, UK
| | - Ji Ma
- Center for Advancing Electronics Dresden (cfaed), Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, Mommsenstraße 4, 01069 Dresden, Germany
| | - Junzhi Liu
- Center for Advancing Electronics Dresden (cfaed), Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, Mommsenstraße 4, 01069 Dresden, Germany
| | - Michael Slota
- Department of Materials, University of Oxford, 16 Parks Road, OX1 3PH Oxford, UK
| | - Akimitsu Narita
- Max Planck Institut für Polymerforschung, Ackermannweg 10, 55128 Mainz, Germany
| | - William K. Myers
- Inorganic Chemistry, University of Oxford, South Parks Road, OX1 3QR Oxford, UK
| | - Klaus Müllen
- Max Planck Institut für Polymerforschung, Ackermannweg 10, 55128 Mainz, Germany
| | - Xinliang Feng
- Center for Advancing Electronics Dresden (cfaed), Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, Mommsenstraße 4, 01069 Dresden, Germany
| | - Lapo Bogani
- Department of Materials, University of Oxford, 16 Parks Road, OX1 3PH Oxford, UK
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41
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Liu X, Chen SY, Chen Q, Yao X, Gelléri M, Ritz S, Kumar S, Cremer C, Landfester K, Müllen K, Parekh SH, Narita A, Bonn M. Nanographenes: Ultrastable, Switchable, and Bright Probes for Super-Resolution Microscopy. Angew Chem Int Ed Engl 2019; 59:496-502. [PMID: 31657497 PMCID: PMC6972658 DOI: 10.1002/anie.201909220] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Indexed: 01/03/2023]
Abstract
Super‐resolution fluorescence microscopy has enabled important breakthroughs in biology and materials science. Implementations such as single‐molecule localization microscopy (SMLM) and minimal emission fluxes (MINFLUX) microscopy in the localization mode exploit fluorophores that blink, i.e., switch on and off, stochastically. Here, we introduce nanographenes, namely large polycyclic aromatic hydrocarbons that can also be regarded as atomically precise graphene quantum dots, as a new class of fluorophores for super‐resolution fluorescence microscopy. Nanographenes exhibit outstanding photophysical properties: intrinsic blinking even in air, excellent fluorescence recovery, and stability over several months. As a proof of concept for super‐resolution applications, we use nanographenes in SMLM to generate 3D super‐resolution images of silica nanocracks. Our findings open the door for the widespread application of nanographenes in super‐resolution fluorescence microscopy.
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Affiliation(s)
- Xiaomin Liu
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Shih-Ya Chen
- Institute of Molecular Biology gGmbH (IMB), Mainz, Germany
| | - Qiang Chen
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Xuelin Yao
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Márton Gelléri
- Institute of Molecular Biology gGmbH (IMB), Mainz, Germany
| | - Sandra Ritz
- Institute of Molecular Biology gGmbH (IMB), Mainz, Germany
| | - Sachin Kumar
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany.,Department of Biomedical Engineering, University of Texas at Austin, Austin, TX, USA
| | - Christoph Cremer
- Institute of Molecular Biology gGmbH (IMB), Mainz, Germany.,Department of Physics, University of Mainz (JGU), Mainz, Germany.,Institute for Pharmacy and Molecular Biotechnology (IPMB), and, Kirchhoff Institute for Physics (KIP), University of Heidelberg, Heidelberg, Germany
| | - Katharina Landfester
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Klaus Müllen
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany.,Institute of Physical Chemistry, Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Sapun H Parekh
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany.,Department of Biomedical Engineering, University of Texas at Austin, Austin, TX, USA
| | - Akimitsu Narita
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany.,Organic and Carbon Nanomaterials Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| | - Mischa Bonn
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
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42
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Liu X, Chen S, Chen Q, Yao X, Gelléri M, Ritz S, Kumar S, Cremer C, Landfester K, Müllen K, Parekh SH, Narita A, Bonn M. Nanographene: ultrastabile, schaltbare und helle Sonden für die hochauflösende Mikroskopie. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201909220] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Xiaomin Liu
- Max-Planck-Institut für Polymerforschung Ackermannweg 10 55128 Mainz Deutschland
| | - Shih‐Ya Chen
- Institut für Molekularbiologie gGmbH (IMB) Mainz Deutschland
| | - Qiang Chen
- Max-Planck-Institut für Polymerforschung Ackermannweg 10 55128 Mainz Deutschland
| | - Xuelin Yao
- Max-Planck-Institut für Polymerforschung Ackermannweg 10 55128 Mainz Deutschland
| | - Márton Gelléri
- Institut für Molekularbiologie gGmbH (IMB) Mainz Deutschland
| | - Sandra Ritz
- Institut für Molekularbiologie gGmbH (IMB) Mainz Deutschland
| | - Sachin Kumar
- Max-Planck-Institut für Polymerforschung Ackermannweg 10 55128 Mainz Deutschland
- Department of Biomedical Engineering University of Texas at Austin Austin TX USA
| | - Christoph Cremer
- Institut für Molekularbiologie gGmbH (IMB) Mainz Deutschland
- Physikalisches Institut Universität Mainz (JGU) Mainz Deutschland
- Institut für Pharmazie und Molekulare Biotechnologie (IPMB), und Kirchhoff-Institut für Physik (KIP) Universität Heidelberg Heidelberg Deutschland
| | - Katharina Landfester
- Max-Planck-Institut für Polymerforschung Ackermannweg 10 55128 Mainz Deutschland
| | - Klaus Müllen
- Max-Planck-Institut für Polymerforschung Ackermannweg 10 55128 Mainz Deutschland
- Institut für Physikalische Chemie Johannes Gutenberg-Universität Mainz Mainz Deutschland
| | - Sapun H. Parekh
- Max-Planck-Institut für Polymerforschung Ackermannweg 10 55128 Mainz Deutschland
- Department of Biomedical Engineering University of Texas at Austin Austin TX USA
| | - Akimitsu Narita
- Max-Planck-Institut für Polymerforschung Ackermannweg 10 55128 Mainz Deutschland
- Organic and Carbon Nanomaterials Unit Okinawa Institute of Science and Technology Graduate University Okinawa Japan
| | - Mischa Bonn
- Max-Planck-Institut für Polymerforschung Ackermannweg 10 55128 Mainz Deutschland
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43
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Chen S, Ullah N, Zhao Y, Zhang R. Nonradiative Excited-State Decay via Conical Intersection in Graphene Nanostructures. Chemphyschem 2019; 20:2754-2758. [PMID: 31489973 DOI: 10.1002/cphc.201900532] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Revised: 07/15/2019] [Indexed: 11/06/2022]
Abstract
Chemical groups are known to tune the luminescent efficiencies of graphene-related nanomaterials, but some species, including the epoxide group (-COC-), are suspected to act as emission-quenching sites. Herein, by performing nonadiabatic excited-state dynamics simulations, we reveal a fast (within 300 fs) nonradiative excited-state decay of a graphene epoxide nanostructure from the lowest excited singlet (S1 ) state to the ground (S0 ) state via a conical intersection (CI), at which the energy difference between the S1 and S0 states is approximately zero. This CI is induced after breaking one C-O bond at the -COC- moiety during excited-state structural relaxation. This study ascertains the role of epoxide groups in inducing the nonradiative recombination of the excited electron-hole, providing important insights into the CI-promoted nonradiative de-excitations and the luminescence tuning of relevant materials. In addition, it shows the feasibility of utilizing nonadiabatic excited-state dynamics simulations to investigate the photophysical processes of the excited states of graphene nanomaterials.
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Affiliation(s)
- Shunwei Chen
- Department of Physics, City University of Hong Kong, Hong Kong SAR, China.,School of Materials Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, China
| | - Naeem Ullah
- Department of Physics, City University of Hong Kong, Hong Kong SAR, China
| | - Yanling Zhao
- Department of Physics, City University of Hong Kong, Hong Kong SAR, China.,Shenzhen Research Institute, City University of Hong Kong, Shenzhen, China
| | - Ruiqin Zhang
- Department of Physics, City University of Hong Kong, Hong Kong SAR, China.,Shenzhen Research Institute, City University of Hong Kong, Shenzhen, China
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44
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Ihara T, Miki S, Yamada T, Kaji T, Otomo A, Hosako I, Terai H. Superior properties in room-temperature colloidal-dot quantum emitters revealed by ultralow-dark-count detections of temporally-purified single photons. Sci Rep 2019; 9:15941. [PMID: 31685915 PMCID: PMC6828765 DOI: 10.1038/s41598-019-52377-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 10/11/2019] [Indexed: 11/22/2022] Open
Abstract
The realization of high-quality quantum emitters that can operate at room temperature is important for accelerating the application of quantum technologies, such as quantum communication, quantum information processing, and quantum metrology. In this work, we study the photon-antibunching properties on room-temperature emission from individual colloidal quantum dots (CQDs) using superconducting-nanowire single-photon detectors and temporal filtering of the photoluminescence decay curve. We find that high single-photon purities and high photon-generation rates can be simultaneously achieved by removing the signals originating from the sequential two-photon emission of biexcitons created by multiple excitation pulses. We successfully demonstrate that the ultrahigh performance of the room-temperature single-photon sources showing g(2)(0) ≪ 10−2 can be confirmed by the ultralow-dark-count detection of the temporally purified single photons. These findings provide strong evidence for the attractiveness of CQDs as candidates for high-quality room-temperature quantum light sources.
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Affiliation(s)
- Toshiyuki Ihara
- Advanced ICT Research Institute, National Institute of Information and Communications Technology, 588-2, Iwaoka, Nishi-ku, Kobe, Hyogo, 651-2492, Japan.
| | - Shigehito Miki
- Advanced ICT Research Institute, National Institute of Information and Communications Technology, 588-2, Iwaoka, Nishi-ku, Kobe, Hyogo, 651-2492, Japan.,Kobe University, 1-1, Rokkodai-cho, Nada-ku, Kobe, Hyogo, 657-8501, Japan
| | - Toshiki Yamada
- Advanced ICT Research Institute, National Institute of Information and Communications Technology, 588-2, Iwaoka, Nishi-ku, Kobe, Hyogo, 651-2492, Japan
| | - Takahiro Kaji
- Advanced ICT Research Institute, National Institute of Information and Communications Technology, 588-2, Iwaoka, Nishi-ku, Kobe, Hyogo, 651-2492, Japan
| | - Akira Otomo
- Advanced ICT Research Institute, National Institute of Information and Communications Technology, 588-2, Iwaoka, Nishi-ku, Kobe, Hyogo, 651-2492, Japan
| | - Iwao Hosako
- Advanced ICT Research Institute, National Institute of Information and Communications Technology, 588-2, Iwaoka, Nishi-ku, Kobe, Hyogo, 651-2492, Japan
| | - Hirotaka Terai
- Advanced ICT Research Institute, National Institute of Information and Communications Technology, 588-2, Iwaoka, Nishi-ku, Kobe, Hyogo, 651-2492, Japan
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45
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Chen Y, Marty L, Bendiab N. New Light on Molecule-Nanotube Hybrids. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1902917. [PMID: 31553098 DOI: 10.1002/adma.201902917] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 07/16/2019] [Indexed: 06/10/2023]
Abstract
Optoelectronics benefits from outstanding new nanomaterials that provide emission and detection in the visible and near-infrared range, photoswitches, two level systems for single photon emission, etc. Among these, carbon nanotubes are envisioned as game changers despite difficult handling and control over chirality burdening their use. However, recent breakthroughs on hybrid carbon nanotubes have established nanotubes as pioneers for a new family of building blocks for optics and quantum optics. Functionalization of carbon nanotubes with molecules or polymers not only preserves the nanotube properties from the environment, but also promotes new performance abilities to the resulting hybrids. Photoluminescence and Raman signals are enhanced in the hybrids, which questions the nature of the electronic coupling between nanotube and molecules. Furthermore, coupling to optical cavities dramatically enhances single photon emission, which operates up to room temperature. This new light on nanotube hybrids shows their potential to push optoelectronics a step forward.
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Affiliation(s)
- Yani Chen
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, P. R. China
- Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, P. R. China
- Univ. Grenoble Alpes, CNRS, Grenoble INP, Institut Néel, 38000, Grenoble, France
| | - Laëtitia Marty
- Univ. Grenoble Alpes, CNRS, Grenoble INP, Institut Néel, 38000, Grenoble, France
| | - Nedjma Bendiab
- Univ. Grenoble Alpes, CNRS, Grenoble INP, Institut Néel, 38000, Grenoble, France
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46
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Dervishi E, Ji Z, Htoon H, Sykora M, Doorn SK. Raman spectroscopy of bottom-up synthesized graphene quantum dots: size and structure dependence. NANOSCALE 2019; 11:16571-16581. [PMID: 31460557 DOI: 10.1039/c9nr05345j] [Citation(s) in RCA: 82] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Graphene quantum dots (GQDs) have attracted significant interest as synthetically tunable optoelectronic and photonic materials that can also serve as model systems for understanding size-dependent behaviors of related graphene structures such as nanoribbons. We present a Raman spectroscopy study of bottom-up synthesized GQDs with lateral dimensions between 0.97 to 1.62 nm, well-defined (armchair) edge type, and fully benzenoid structures. For a better understanding of observed size-dependent trends, the study is extended to larger graphene structures including nano-graphene platelets (>25 nm) and large-area graphene. Raman spectra of GQDs reveal the presence of D and G bands, as well as higher order modes (2D, D + G, and 2G). The D and G band frequencies and intensity were found to increase as GQD size increases, while higher order modes (2D, D + G, and 2G) also increased in intensity and became more well-defined. The integrated intensity ratios of D and G bands (ID/IG) increase as the size of the GQDs approaches 2 nm and rapidly decrease for larger graphene structures. We present a quantitative comparison of ID/IG ratios for the GQDs and for defects introduced into large area graphenes through ion bombardment, for which inter-defect distances are comparable to the sizes of GQDs studied here. Close agreement suggests the ID/IG ratio as a size diagnostic for other nanographenes. Finally, we show that Raman spectroscopy is also a good diagnostic tool for monitoring the formation of bottom-up synthesized GQDs.
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Affiliation(s)
- Enkeleda Dervishi
- Materials Physics and Applications Division, Center for Integrated Nanotechnologies, Los Alamos, New Mexico 87545, USA.
| | - Zhiqiang Ji
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
| | - Han Htoon
- Materials Physics and Applications Division, Center for Integrated Nanotechnologies, Los Alamos, New Mexico 87545, USA.
| | - Milan Sykora
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
| | - Stephen K Doorn
- Materials Physics and Applications Division, Center for Integrated Nanotechnologies, Los Alamos, New Mexico 87545, USA.
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Abstract
Bilayer graphene consists of two stacked graphene layers bound together by van der Waals interaction. As the molecular analog of bilayer graphene, molecular bilayer graphene (MBLG) can offer useful insights into the structural and functional properties of bilayer graphene. However, synthesis of MBLG, which requires discrete assembly of two graphene fragments, has proved to be challenging. Here, we show the synthesis and characterization of two structurally well-defined MBLGs, both consisting of two π-π stacked nanographene sheets. We find they have excellent stability against variation of concentration, temperature and solvents. The MBLGs show sharp absorption and emission peaks, and further time-resolved spectroscopic studies reveal drastically different lifetimes for the bright and dark Davydov states in these MBLGs.
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Scharl T, Ferrer-Ruiz A, Saura-Sanmartín A, Rodríguez-Pérez L, Herranz MÁ, Martín N, Guldi DM. Charge transfer in graphene quantum dots coupled with tetrathiafulvalenes. Chem Commun (Camb) 2019; 55:3223-3226. [PMID: 30806381 DOI: 10.1039/c8cc09990a] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Water-soluble fluorescent graphene quantum dots have been successfully prepared through a top-down approach, that is, starting with graphite, and covalently functionalizing it with π-extended tetrathiafulvalene. Charge transfer investigations reveal noticeably slower charge recombination when compared with exTTF nanoconjugates featuring carbon nanodots, for which a larger presence of trap states is observed.
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Affiliation(s)
- Tobias Scharl
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander Universität Erlangen-Nürberg, Egerlandstr. 3, 91058 Erlangen, Germany.
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Ji Z, Dervishi E, Doorn SK, Sykora M. Size-Dependent Electronic Properties of Uniform Ensembles of Strongly Confined Graphene Quantum Dots. J Phys Chem Lett 2019; 10:953-959. [PMID: 30764609 DOI: 10.1021/acs.jpclett.9b00119] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The electronic structure of a series of bottom-up synthesized graphene quantum dots (GQDs) smaller than 2 nm was investigated by spectroelectrochemistry, yielding insights not previously available from ensemble-level studies. The results show that for the strongly confined GQDs the dependence of the band gap on the GQD size deviates from the prediction of the standard Dirac Fermion model but agrees well with the models explicitly accounting for the electron-electron and electron-hole interactions. The HOMO/LUMO energy levels are found to be distributed nearly symmetrically around the 0 V value versus normal hydrogen electrode (NHE), becoming more positive/negative, respectively, with increasing GQD size. The exciton binding energies are found to follow power dependence on the number of carbon atoms per GQD, with the experimental values falling within the range of ∼0.1 to ∼0.6 eV. Given the broad accessibility of the described experimental tools and methods, our work opens a path to a more systematic examination of quantum confinement effects in GQDs.
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Affiliation(s)
- Zhiqiang Ji
- Chemistry Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Enkeleda Dervishi
- Materials Physics and Applications Division, Center for Integrated Nanotechnologies , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Stephen K Doorn
- Materials Physics and Applications Division, Center for Integrated Nanotechnologies , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Milan Sykora
- Chemistry Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
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