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Tian Y, Yang D, Ma Y, Li Z, Li J, Deng Z, Tian H, Yang H, Sun S, Li J. Spatiotemporal Visualization of Photogenerated Carriers on an Avalanche Photodiode Surface Using Ultrafast Scanning Electron Microscopy. NANOMATERIALS (BASEL, SWITZERLAND) 2024; 14:310. [PMID: 38334581 PMCID: PMC10857202 DOI: 10.3390/nano14030310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 01/25/2024] [Accepted: 01/30/2024] [Indexed: 02/10/2024]
Abstract
The spatiotemporal evolution of photogenerated charge carriers on surfaces and at interfaces of photoactive materials is an important issue for understanding fundamental physical processes in optoelectronic devices and advanced materials. Conventional optical probe-based microscopes that provide indirect information about the dynamic behavior of photogenerated carriers are inherently limited by their poor spatial resolution and large penetration depth. Herein, we develop an ultrafast scanning electron microscope (USEM) with a planar emitter. The photoelectrons per pulse in this USEM can be two orders of magnitude higher than that of a tip emitter, allowing the capture of high-resolution spatiotemporal images. We used the contrast change of the USEM to examine the dynamic nature of surface carriers in an InGaAs/InP avalanche photodiode (APD) after femtosecond laser excitation. It was observed that the photogenerated carriers showed notable longitudinal drift, lateral diffusion, and carrier recombination associated with the presence of photovoltaic potential at the surface. This work demonstrates an in situ multiphysics USEM platform with the capability to stroboscopically record carrier dynamics in space and time.
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Affiliation(s)
- Yuan Tian
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China; (Y.T.); (D.Y.); (Y.M.); (Z.L.); (J.L.); (Z.D.); (H.T.); (H.Y.); (S.S.)
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Dong Yang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China; (Y.T.); (D.Y.); (Y.M.); (Z.L.); (J.L.); (Z.D.); (H.T.); (H.Y.); (S.S.)
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yu Ma
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China; (Y.T.); (D.Y.); (Y.M.); (Z.L.); (J.L.); (Z.D.); (H.T.); (H.Y.); (S.S.)
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhongwen Li
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China; (Y.T.); (D.Y.); (Y.M.); (Z.L.); (J.L.); (Z.D.); (H.T.); (H.Y.); (S.S.)
| | - Jun Li
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China; (Y.T.); (D.Y.); (Y.M.); (Z.L.); (J.L.); (Z.D.); (H.T.); (H.Y.); (S.S.)
| | - Zhen Deng
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China; (Y.T.); (D.Y.); (Y.M.); (Z.L.); (J.L.); (Z.D.); (H.T.); (H.Y.); (S.S.)
| | - Huanfang Tian
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China; (Y.T.); (D.Y.); (Y.M.); (Z.L.); (J.L.); (Z.D.); (H.T.); (H.Y.); (S.S.)
| | - Huaixin Yang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China; (Y.T.); (D.Y.); (Y.M.); (Z.L.); (J.L.); (Z.D.); (H.T.); (H.Y.); (S.S.)
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shuaishuai Sun
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China; (Y.T.); (D.Y.); (Y.M.); (Z.L.); (J.L.); (Z.D.); (H.T.); (H.Y.); (S.S.)
- Songshan Lake Materials Laboratory, Dongguan 523808, China
| | - Jianqi Li
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China; (Y.T.); (D.Y.); (Y.M.); (Z.L.); (J.L.); (Z.D.); (H.T.); (H.Y.); (S.S.)
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- Songshan Lake Materials Laboratory, Dongguan 523808, China
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2
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Amuah EB, Siddiqui KM, Monti M, Johnson AS, Wall SE. Determination and correction of spectral phase from principal component analysis of coherent phonons. OPTICS EXPRESS 2024; 32:3817-3825. [PMID: 38297594 DOI: 10.1364/oe.514141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Accepted: 01/11/2024] [Indexed: 02/02/2024]
Abstract
Measuring the spectral phase of a pulse is key for performing wavelength resolved ultrafast measurements in the few femtosecond regime. However, accurate measurements in real experimental conditions can be challenging. We show that the reflectivity change induced by coherent phonons in a quantum material can be used to infer the spectral phase of an optical probe pulse with few-femtosecond accuracy.
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3
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Zheng Y, Venkatesh R, Callaway CP, Viersen C, Fagbohungbe KH, Liu AL, Risko C, Reichmanis E, Silva-Acuña C. Chain Conformation and Exciton Delocalization in a Push-Pull Conjugated Polymer. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2023; 35:10258-10267. [PMID: 38107193 PMCID: PMC10720347 DOI: 10.1021/acs.chemmater.3c02665] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 10/24/2023] [Indexed: 12/19/2023]
Abstract
Linear and nonlinear optical line shapes reveal details of excitonic structure in polymer semiconductors. We implement absorption, photoluminescence, and transient absorption spectroscopies in DPP-DTT, an electron push-pull copolymer, to explore the relationship between their spectral line shapes and chain conformation, deduced from resonance Raman spectroscopy and from ab initio calculations. The viscosity of precursor polymer solutions before film casting displays a transition that suggests gel formation above a critical concentration. Upon crossing this viscosity deflection concentration, the line shape analysis of the absorption spectra within a photophysical aggregate model reveals a gradual increase in interchain excitonic coupling. We also observe a red-shifted and line-narrowed steady-state photoluminescence spectrum along with increasing resonance Raman intensity in the stretching and torsional modes of the dithienothiophene unit, which suggests a longer exciton coherence length along the polymer-chain backbone. Furthermore, we observe a change of line shape in the photoinduced absorption component of the transient absorption spectrum. The derivative-like line shape may originate from two possibilities: a new excited-state absorption or Stark effect, both of which are consistent with the emergence of a high-energy shoulder as seen in both photoluminescence and absorption spectra. Therefore, we conclude that the exciton is more dispersed along the polymer chain backbone with increasing concentrations, leading to the hypothesis that polymer chain order is enhanced when the push-pull polymers are processed at higher concentrations. Thus, tuning the microscopic chain conformation by concentration would be another factor of interest when considering the polymer assembly pathways for pursuing large-area and high-performance organic optoelectronic devices.
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Affiliation(s)
- Yulong Zheng
- School
of Chemistry and Biochemistry, Georgia Institute
of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332, United States
| | - Rahul Venkatesh
- School
of Chemical and Biomolecular Engineering, Georgia Institute of Technology, 311 Ferst Drive NW, Atlanta, Georgia 30332, United States
| | - Connor P. Callaway
- Department
of Chemistry and Center for Applied Energy Research, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Campbell Viersen
- School
of Chemistry and Biochemistry, Georgia Institute
of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332, United States
| | - Kehinde H. Fagbohungbe
- Department
of Chemistry and Center for Applied Energy Research, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Aaron L. Liu
- School
of Chemical and Biomolecular Engineering, Georgia Institute of Technology, 311 Ferst Drive NW, Atlanta, Georgia 30332, United States
| | - Chad Risko
- Department
of Chemistry and Center for Applied Energy Research, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Elsa Reichmanis
- Department
of Chemical & Biomolecular Engineering, Lehigh University, 124 East Morton Street, Bethlehem, Pennsylvania 18015, United States
| | - Carlos Silva-Acuña
- School
of Chemistry and Biochemistry, Georgia Institute
of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332, United States
- School
of Physics, Georgia Institute of Technology, 837 State Street, Atlanta, Georgia 30332, United States
- School
of Materials Science and Engineering, Georgia
Institute of Technology, North Avenue, Atlanta, Georgia 30332, United States
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4
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An X, Wei C, Bai L, Zhou J, Wang L, Han Y, Sun L, Lin J, Liu H, Li J, Xu M, Ling H, Xie L, Huang W. Photoexcitation dynamics and energy engineering in supramolecular doping of organic conjugated molecules. LIGHT, SCIENCE & APPLICATIONS 2023; 12:30. [PMID: 36720850 PMCID: PMC9889348 DOI: 10.1038/s41377-022-01062-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 12/15/2022] [Accepted: 12/15/2022] [Indexed: 06/18/2023]
Abstract
Doping and blending strategies are crucial means to precisely control the excited states and energy level in conjugated molecular systems. However, effective models and platforms are rarely proposed to systematically explore the effects of the formation of trapped doped centers on heterogeneous structures, energy level and ultrafast photophysical process. Herein, for deeply understanding the impact of molecular doping in film energy levels and photoexcitation dynamics, we set a supramolecular N-B coordination composed by the conjugated molecules of pyridine functionalized diarylfluorene (host material), named as ODPF-Phpy and ODPF-(Phpy)2, and the molecule of tris(perfluorophenyl)borane (BCF) (guest material). The generation of the molecular-level coordination bond increased the binding energy of N atoms and tuned the band-gap, leading to a new fluorescent emission center with longer excitation wavelength and emission wavelength. The intermolecular Förster resonance energy transfer (FRET) in blending films make it present inconsistent fluorescent behaviors compared to that in solution. The charge transfer (CT) state of N-B coordinated compounds and the changed dielectric constant of blending films resulted in a large PL spectra red-shift with the increased dopant ratio, causing a wide-tunable fluorescent color. The excited state behaviors of two compounds in blending system was further investigated by the transient absorption (TA) spectroscopy. Finally, we found supramolecular coordination blending can effectively improve the films' photoluminescence quantum yield (PLQY) and conductivity. We believe this exploration in the internal coordination mechanisms would deepen the insights about doped semiconductors and is helpful in developing novel high-efficient fluorescent systems.
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Affiliation(s)
- Xiang An
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, 211816, China
| | - Chuanxin Wei
- State Key Laboratory of Organic Electronics and Information Displays & Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing, 210023, China
| | - Lubing Bai
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, 211816, China
| | - Jun Zhou
- College of Science and Institute of New Energy, China University of Petroleum (East China), Qingdao, 266580, China
| | - Le Wang
- State Key Laboratory of Organic Electronics and Information Displays & Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing, 210023, China
| | - Yamin Han
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, 211816, China
| | - Lili Sun
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, 211816, China
| | - Jinyi Lin
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, 211816, China.
- Shaanxi Institute of Flexible Electronics (SIFE), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi'an, 710072, Shaanxi, China.
| | - Heyuan Liu
- College of Science and Institute of New Energy, China University of Petroleum (East China), Qingdao, 266580, China
| | - Jiewei Li
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, 211816, China
| | - Man Xu
- State Key Laboratory of Organic Electronics and Information Displays & Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing, 210023, China
| | - Haifeng Ling
- State Key Laboratory of Organic Electronics and Information Displays & Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing, 210023, China
| | - Linghai Xie
- State Key Laboratory of Organic Electronics and Information Displays & Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing, 210023, China
- Shaanxi Institute of Flexible Electronics (SIFE), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi'an, 710072, Shaanxi, China
| | - Wei Huang
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, 211816, China.
- Shaanxi Institute of Flexible Electronics (SIFE), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi'an, 710072, Shaanxi, China.
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5
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Zhang J, Zhu B, Zhang L, Yu J. Femtosecond transient absorption spectroscopy investigation into the electron transfer mechanism in photocatalysis. Chem Commun (Camb) 2023; 59:688-699. [PMID: 36598049 DOI: 10.1039/d2cc06300j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Femtosecond transient absorption spectroscopy (fs-TAS) is a powerful technique for monitoring the electron transfer kinetics in photocatalysis. Several important works have successfully elucidated the electron transfer mechanism in heterojunction photocatalysts (HPs) using fs-TAS measurements, and thus a timely summary of recent advances is essential. This feature article starts with a thorough interpretation of the operating principle of fs-TAS equipment, and the fundamentals of the fs-TAS spectra. Subsequently, the applications of fs-TAS in analyzing the dynamics of photogenerated carriers in semiconductor/metal HPs, semiconductor/carbon HPs, semiconductor/semiconductor HPs, and multicomponent HPs are discussed in sequence. Finally, the significance of fs-TAS in revealing the ultrafast interfacial electron transfer process in HPs is summarized, and further research on the applications of fs-TAS in photocatalysis is proposed. This feature article will provide deep insight into the mechanism of the enhanced photocatalytic performance of HPs from the perspective of electron transfer kinetics.
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Affiliation(s)
- Jianjun Zhang
- Laboratory of Solar Fuel, Faculty of Materials Science and Chemistry, China University of Geosciences, 68 Jincheng Street, Wuhan 430078, P. R. China.
| | - Bicheng Zhu
- Laboratory of Solar Fuel, Faculty of Materials Science and Chemistry, China University of Geosciences, 68 Jincheng Street, Wuhan 430078, P. R. China.
| | - Liuyang Zhang
- Laboratory of Solar Fuel, Faculty of Materials Science and Chemistry, China University of Geosciences, 68 Jincheng Street, Wuhan 430078, P. R. China.
| | - Jiaguo Yu
- Laboratory of Solar Fuel, Faculty of Materials Science and Chemistry, China University of Geosciences, 68 Jincheng Street, Wuhan 430078, P. R. China.
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6
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Schwarzl R, Heim P, Schiek M, Grimaldi D, Hohenau A, Krenn JR, Koch M. Transient absorption microscopy setup with multi-ten-kilohertz shot-to-shot subtraction and discrete Fourier analysis. OPTICS EXPRESS 2022; 30:34385-34395. [PMID: 36242451 DOI: 10.1364/oe.466272] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 07/18/2022] [Indexed: 06/16/2023]
Abstract
Recording of transient absorption microscopy images requires fast detection of minute optical density changes, which is typically achieved with high-repetition-rate laser sources and lock-in detection. Here, we present a highly flexible and cost-efficient detection scheme based on a conventional photodiode and an USB oscilloscope with MHz bandwidth, that deviates from the commonly used lock-in setup and achieves benchmark sensitivity. Our scheme combines shot-to-shot evaluation of pump-probe and probe-only measurements, a home-built photodetector circuit optimized for low pulse energies applying low-pass amplification, and a custom evaluation algorithm based on Fourier transformation. Advantages of this approach include abilities to simultaneously monitor multiple pulse modulation frequencies, implement the detection of additional pulse sequences (e.g., pump-only), and expand to multiple parallel detection channels for wavelength-dispersive probing. With a 40 kHz repetition-rate laser system powering two non-collinear optical parametric amplifiers for wide tuneability, we find that laser pulse fluctuations limit the sensitivity of the setup, while the detection scheme has negligible contribution. We demonstrate the 2-D imaging performance of our transient absorption microscope with studies on micro-crystalline molecular thin films.
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7
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Zu G, Li S, He J, Zhang H, Fu H. Amplified Spontaneous Emission from Organic Phosphorescence Emitters. J Phys Chem Lett 2022; 13:5461-5467. [PMID: 35686987 DOI: 10.1021/acs.jpclett.2c01379] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Organic gain materials (OGMs) currently used in organic lasers and optical amplifiers are focused on singlet-fluorescence materials, while triplet-phosphorescence-based OGMs have hardly been developed yet. Herein, we report a novel pure organic phosphorescence gain molecule (SBP) for optical amplification by stimulated emission from triplet states. The introduction of the benzophenone carbonyl group and sulfur atoms increases the spin orbit coupling constant of SBP, which accelerates the intersystem crossing (ISC) and phosphorescence processes. Experimental and theoretical results verify that the formation of the H-type dimer aggregate decreases the fluorescence radiation rate while accelerating the ISC rate, also enhancing the phosphorescence emission of SBP. Doping SBP molecules into a PMMA matrix can stabilize triplet excitons, yielding the maximum phosphorescence quantum yield of 18.9%. We realized triplet phosphorescent amplified spontaneous emission (ASE) at 557 nm from 30.0 wt % SBP@PMMA samples. Our results provide a novel strategy to develop triplet phosphor OGMs.
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Affiliation(s)
- Guo Zu
- Institute of Molecule Plus, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin 300072, P. R. China
| | - Shuai Li
- Institute of Molecule Plus, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin 300072, P. R. China
| | - Jingping He
- Beijing Key Laboratory for Optical Materials and Photonic Devices, Department of Chemistry, Capital Normal University, Beijing 100048, P. R. China
| | - Haihua Zhang
- Institute of Molecule Plus, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin 300072, P. R. China
| | - Hongbing Fu
- Institute of Molecule Plus, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin 300072, P. R. China
- Beijing Key Laboratory for Optical Materials and Photonic Devices, Department of Chemistry, Capital Normal University, Beijing 100048, P. R. China
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8
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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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9
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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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10
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Zhang Y, Dai J, Zhong X, Zhang D, Zhong G, Li J. Probing Ultrafast Dynamics of Ferroelectrics by Time-Resolved Pump-Probe Spectroscopy. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:e2102488. [PMID: 34632722 PMCID: PMC8596111 DOI: 10.1002/advs.202102488] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 07/29/2021] [Indexed: 05/26/2023]
Abstract
Ferroelectric materials have been a key research topic owing to their wide variety of modern electronic and photonic applications. For the quick exploration of higher operating speed, smaller size, and superior efficiencies of novel ferroelectric devices, the ultrafast dynamics of ferroelectrics that directly reflect their respond time and lifetimes have drawn considerable attention. Driven by time-resolved pump-probe spectroscopy that allows for probing, controlling, and modulating dynamic processes of ferroelectrics in real-time, much research efforts have been made to understand and exploit the ultrafast dynamics of ferroelectric. Herein, the current state of ultrafast dynamic features of ferroelectrics tracked by time-resolved pump-probe spectroscopy is reviewed, which includes ferroelectrics order parameters of polarization, lattice, spin, electronic excitation, and their coupling. Several potential perspectives and possible further applications combining ultrafast pump-probe spectroscopy and ferroelectrics are also presented. This review offers a clear guidance of ultrafast dynamics of ferroelectric orders, which may promote the rapid development of next-generation devices.
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Affiliation(s)
- Yuan Zhang
- Shenzhen Key Laboratory of Nanobiomechanics, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, 518055, China
| | - Junfeng Dai
- Shenzhen Institute for Quantum Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Xiangli Zhong
- School of Materials Science and Engineering, Xiangtan University, Xiangtan, Hunan, 411105, China
| | - Dongwen Zhang
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha, Hunan, 410073, China
| | - Gaokuo Zhong
- Shenzhen Key Laboratory of Nanobiomechanics, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, 518055, China
| | - Jiangyu Li
- Shenzhen Key Laboratory of Nanobiomechanics, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, 518055, China
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
- Guangdong Provincial Key Laboratory of Functional Oxide Materials and Devices, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
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11
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Ardekani H, Wilmington RL, Vutukuru M, Chen Z, Brandt R, Swan AK, Gundogdu K. Broadband micro-transient absorption spectroscopy enabled by improved lock-in amplification. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2021; 92:104706. [PMID: 34717443 DOI: 10.1063/5.0060244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 09/13/2021] [Indexed: 06/13/2023]
Abstract
Recent breakthroughs in material development have increased the demand for characterization methods capable of probing nanoscale features on ultrafast time scales. As the sample reduces to atomically thin levels, an extremely low-level signal limits the feasibility of many experiments. Here, we present an affordable and easy-to-implement solution to expand the maximum sensitivity of lock-in detection systems used in transient absorption spectroscopy by multiple orders of magnitude. By implementation of a tuned RC circuit to the output of an avalanche photodiode, electric pulse shaping allows for vastly improved lock-in detection. Furthermore, a carefully designed "peak detector" circuit provides additional pulse shaping benefits, resulting in even more lock-in detection signal enhancement. We demonstrate the improvement of lock-in detection with each of these schemes by performing benchmark measurements of a white-light continuum signal and micro-transient absorption spectroscopy on a few-layer transition metal dichalcogenide sample. Our results show the practicality of ultrafast pump-probe spectroscopy for many high-sensitivity experimental schemes.
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Affiliation(s)
- Hossein Ardekani
- Department of Physics, NC State University, Raleigh, North Carolina 27695, USA
| | - Ryan L Wilmington
- Department of Physics, NC State University, Raleigh, North Carolina 27695, USA
| | - Mounika Vutukuru
- Department of Electrical and Computer Engineering, Boston University, Boston, Massachusetts 02215, USA
| | - Zhuofa Chen
- Department of Electrical and Computer Engineering, Boston University, Boston, Massachusetts 02215, USA
| | - Ryan Brandt
- Department of Electrical Engineering, Stanford University, Stanford, California 94305, USA
| | - Anna K Swan
- Department of Electrical and Computer Engineering, Boston University, Boston, Massachusetts 02215, USA
| | - Kenan Gundogdu
- Department of Physics, NC State University, Raleigh, North Carolina 27695, USA
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12
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Steiner AM, Lissel F, Fery A, Lauth J, Scheele M. Perspektiven gekoppelter organisch‐anorganischer Nanostrukturen für Ladungs‐ und Energietransferanwendungen. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.201916402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Anja Maria Steiner
- Institut Physikalische Chemie und Physik der Polymere Leibniz-Institut für Polymerforschung Hohe Str. 6 01069 Dresden Deutschland
| | - Franziska Lissel
- Institut Makromolekulare Chemie Leibniz-Institut für Polymerforschung Hohe Str. 6 01069 Dresden Deutschland
- Technische Universität Dresden Mommsenstr. 4 01064 Dresden Deutschland
| | - Andreas Fery
- Institut Physikalische Chemie und Physik der Polymere Leibniz-Institut für Polymerforschung Hohe Str. 6 01069 Dresden Deutschland
- Technische Universität Dresden Mommsenstr. 4 01064 Dresden Deutschland
| | - Jannika Lauth
- Leibniz-Universität Hannover Institut für Physikalische Chemie und Elektrochemie Callinstr. 3A 30167 Hannover Deutschland
| | - Marcus Scheele
- Eberhard-Karls-Universität Tübingen Institut für Physikalische und Theoretische Chemie Auf der Morgenstelle 18 72076 Tübingen Deutschland
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13
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Steiner AM, Lissel F, Fery A, Lauth J, Scheele M. Prospects of Coupled Organic-Inorganic Nanostructures for Charge and Energy Transfer Applications. Angew Chem Int Ed Engl 2021; 60:1152-1175. [PMID: 32173981 PMCID: PMC7821299 DOI: 10.1002/anie.201916402] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Indexed: 12/20/2022]
Abstract
We review the field of organic-inorganic nanocomposites with a focus on materials that exhibit a significant degree of electronic coupling across the hybrid interface. These nanocomposites undergo a variety of charge and energy transfer processes, enabling optoelectronic applications in devices which exploit singlet fission, triplet energy harvesting, photon upconversion or hot charge carrier transfer. We discuss the physical chemistry of the most common organic and inorganic components. Based on those we derive synthesis and assembly strategies and design criteria on material and device level with a focus on photovoltaics, spin memories or optical upconverters. We conclude that future research in the field should be directed towards an improved understanding of the binding motif and molecular orientation at the hybrid interface.
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Affiliation(s)
- Anja Maria Steiner
- Institute for Physical Chemistry and Polymer PhysicsLeibniz Institute of Polymer ResearchHohe Str. 601069DresdenGermany
| | - Franziska Lissel
- Institute of Macromolecular ChemistryLeibniz Institute of Polymer ResearchHohe Str. 601069DresdenGermany
- Technische Universität DresdenMommsenstr. 401064DresdenGermany
| | - Andreas Fery
- Institute for Physical Chemistry and Polymer PhysicsLeibniz Institute of Polymer ResearchHohe Str. 601069DresdenGermany
- Technische Universität DresdenMommsenstr. 401064DresdenGermany
| | - Jannika Lauth
- Leibniz Universität HannoverInstitute of Physical Chemistry and ElectrochemistryCallinstr. 3A30167HannoverGermany
| | - Marcus Scheele
- Eberhard Karls-Universität TübingenInstitute of Physical and Theoretical ChemistryAuf der Morgenstelle 1872076TübingenGermany
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14
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Bargigia I, Savagian LR, Österholm AM, Reynolds JR, Silva C. Charge-Transfer Intermediates in the Electrochemical Doping Mechanism of Conjugated Polymers. J Am Chem Soc 2021; 143:294-308. [PMID: 33373233 DOI: 10.1021/jacs.0c10692] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
We address the nature of electrochemically induced charged states in conjugated polymers, their evolution as a function of electrochemical potential, and their coupling to their local environment by means of transient absorption and Raman spectroscopies synergistically performed in situ throughout the electrochemical doping process. In particular, we investigate the fundamental mechanism of electrochemical doping in an oligoether-functionalized 3,4-propylenedioxythiophene (ProDOT) copolymer. The changes embedded in both linear and transient absorption features allow us to identify a precursor electronic state with charge-transfer (CT) character that precedes polaron formation and bulk electronic conductivity. This state is shown to contribute to the ultrafast quenching of both neutral molecular excitations and polarons. Raman spectra relate the electronic transition of this precursor state predominantly to the Cβ-Cβ stretching mode of the thiophene heterocycle. We characterize the coupling of the CT-like state with primary excitons and electrochemically induced charge-separated states, providing insight into the energetic landscape of a heterogeneous polymer-electrolyte system and demonstrating how such coupling depends on environmental parameters, such as polymer structure, electrolyte composition, and environmental polarity.
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Affiliation(s)
- Ilaria Bargigia
- School of Chemistry and Biochemistry, Georgia Tech Polymer Network, Center for Organic Photonics and Electronics, Georgia Institute of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332, United States
| | - Lisa R Savagian
- School of Material Science and Engineering, Georgia Institute of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332, United States
| | - Anna M Österholm
- School of Chemistry and Biochemistry, Georgia Tech Polymer Network, Center for Organic Photonics and Electronics, Georgia Institute of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332, United States
| | - John R Reynolds
- School of Chemistry and Biochemistry, Georgia Tech Polymer Network, Center for Organic Photonics and Electronics, Georgia Institute of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332, United States.,School of Material Science and Engineering, Georgia Institute of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332, United States
| | - Carlos Silva
- School of Chemistry and Biochemistry, Georgia Tech Polymer Network, Center for Organic Photonics and Electronics, Georgia Institute of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332, United States.,School of Material Science and Engineering, Georgia Institute of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332, United States.,School of Physics, Georgia Institute of Technology, Center for Organic Photonics and Electronics, 837 State Street NW, Atlanta, Georgia 30332, United States
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15
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Dumslaff T, Gu Y, Paternò GM, Qiu Z, Maghsoumi A, Tommasini M, Feng X, Scotognella F, Narita A, Müllen K. Hexa- peri-benzocoronene with two extra K-regions in an ortho-configuration. Chem Sci 2020; 11:12816-12821. [PMID: 34094476 PMCID: PMC8163021 DOI: 10.1039/d0sc04649c] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
There are three possible isomers for hexa-peri-hexabenzocoronene (HBC) with two extra K-regions, but only two of them have been reported, namely with the meta- and para-configurations. Herein, we describe the synthesis of HBC 4 with two extra K-regions in the ortho-configuration, forming a longer zigzag edge compared with the other two isomers. The structure of 4 was validated by laser desorption/ionization time-of-flight mass analysis and nuclear magnetic resonance spectra, as well as Raman and infrared spectroscopies supported by density functional theory calculations. The optical properties of 4 were investigated by UV/vis absorption and ultrafast transient absorption spectroscopy. Together with the analysis of aromaticity, the influence of the zigzag edge on the π-conjugation pathway and HOMO–LUMO gaps of the three isomers were investigated. We reported the synthesis of hexa-peri-benzocoronene (HBC) with two extra K-regions adopting an ortho-configuration. The systematical study provides deep insights about the effect of zigzag edge on the π-conjugated pathway and molecular design.![]()
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Affiliation(s)
- Tim Dumslaff
- Max Planck Institute for Polymer Research Ackermannweg 10 55128 Mainz Germany
| | - Yanwei Gu
- Max Planck Institute for Polymer Research Ackermannweg 10 55128 Mainz Germany
| | - Giuseppe M Paternò
- Istituto Italiano di Tecnologia, Center for Nano Science and Technology Milano 20133 Italy
| | - Zijie Qiu
- Max Planck Institute for Polymer Research Ackermannweg 10 55128 Mainz Germany
| | - Ali Maghsoumi
- Dipartimento di Chimica, Materiali e Ingegneria Chimica - Politecnico di Milano Piazza Leonardo da Vinci 32-20133 Milano Italy
| | - Matteo Tommasini
- Dipartimento di Chimica, Materiali e Ingegneria Chimica - Politecnico di Milano Piazza Leonardo da Vinci 32-20133 Milano Italy
| | - Xinliang Feng
- Center for Advancing Electronics Dresden (CFAED), Department of Chemistry and Food Chemistry, Dresden University of Technology Walther-Hempel-Bau Mommsenstrasse 4 01062 Dresden Germany
| | - Francesco Scotognella
- Istituto Italiano di Tecnologia, Center for Nano Science and Technology Milano 20133 Italy
| | - Akimitsu Narita
- Max Planck Institute for Polymer Research Ackermannweg 10 55128 Mainz Germany
| | - Klaus Müllen
- Max Planck Institute for Polymer Research Ackermannweg 10 55128 Mainz Germany
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16
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Nguyen HH, Loukianov AD, Ogilvie JP, Abramavicius D. Two-dimensional electronic Stark spectroscopy of a photosynthetic dimer. J Chem Phys 2020; 153:144203. [PMID: 33086821 DOI: 10.1063/5.0021529] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Stark spectroscopy, which measures changes in the linear absorption of a sample in the presence of an external DC electric field, is a powerful experimental tool for probing the existence of charge-transfer (CT) states in photosynthetic systems. CT states often have small transition dipole moments, making them insensitive to other spectroscopic methods, but are particularly sensitive to Stark spectroscopy due to their large permanent dipole moment. In a previous study, we demonstrated a new experimental method, two-dimensional electronic Stark spectroscopy (2DESS), which combines two-dimensional electronic spectroscopy (2DES) and Stark spectroscopy. In order to understand how the presence of CT states manifest in 2DESS, here, we perform computational modeling and calculations of 2DESS as well as 2DES and Stark spectra, studying a photosynthetic dimer inspired by the photosystem II reaction center. We identify specific cases where qualitatively different sets of system parameters produce similar Stark and 2DES spectra but significantly different 2DESS spectra, showing the potential for 2DESS to aid in identifying CT states and their coupling to excitonic states.
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Affiliation(s)
- Hoang H Nguyen
- Department of Physics, University of Michigan, 450 Church St., Ann Arbor, Michigan 48109, USA
| | - Anton D Loukianov
- Department of Physics, University of Michigan, 450 Church St., Ann Arbor, Michigan 48109, USA
| | - Jennifer P Ogilvie
- Department of Physics, University of Michigan, 450 Church St., Ann Arbor, Michigan 48109, USA
| | - Darius Abramavicius
- Institute of Chemical Physics, Faculty of Physics, Vilnius University, Sauletekio 9-III, 10222 Vilnius, Lithuania
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17
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Determining long-lived photo-excited species in thin-film anthracene derivatives using quasi-continuous wavelength photo-induced absorption. Polym Bull (Berl) 2020. [DOI: 10.1007/s00289-020-03376-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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18
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Li H, Wang X, Zhao X, Li G, Pei F, Zhang H, Tan Y, Chen F. Vacancy-Induced Antibacterial Activity of XS 2-y Quantum Dots against Drug-Resistant Bacteria for Treatment of Bacterial Keratitis. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e2004677. [PMID: 32939988 DOI: 10.1002/smll.202004677] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Indexed: 06/11/2023]
Abstract
Due to the widespread antibiotic-resistant microbes and the slow development in antibiotics, innovative new antibacterial agents are eagerly desired to control infection in the resistance era. Here, it is demonstrated that the antibacterial ability against drug-resistant bacteria can be endowed to transition metal dichalcogenides (XS2 , X = Mo/W) quantum dots by sulfur vacancies, and their application in bacterial keratitis. The sulfur vacancies are generated by the ion irradiation with the controlled influences, which ensures the one-way electron transport from the external environment to XS2 leading to a strong reactive oxygen speciesindependent oxidative stress. With the concentration of 140 µg mL-1 of XS2-0.1 quantum dots, the sterilization efficiency of Gram-positive Staphylococcus aureus and methicillin-resistant Staphylococcus aureus more than 99.9% within 20 min at room temperature in the dark is realized. For biomedical application against bacterial keratitis, it is observed that the occurrence of severe clinical manifestation like ocular perforation can be prevented. This work demonstrates the vacancy as a novel, simple, and effective strategy to tune XS2 as the antibacterial agent with a fast response and no reliance on light that has significant potential therapeutic effects on clinical drug resistant bacterial keratitis.
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Affiliation(s)
- Huiyuan Li
- Department of Ophthalmology, Jinan Central Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, China
| | - Xiao Wang
- Medical Laboratory Diagnosis Center, Jinan Central Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250013, China
| | - Xiaofei Zhao
- Department of Ophthalmology, The Second Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250033, China
| | - Guanhua Li
- Department of Respiratory and Critical Care Medicine, Jinan Central Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250013, China
| | - Fengyan Pei
- Medical Laboratory Diagnosis Center, Jinan Central Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250013, China
| | - Han Zhang
- Department of Ophthalmology, The Second Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250033, China
| | - Yang Tan
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan, Shandong, 250100, China
| | - Feng Chen
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan, Shandong, 250100, China
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19
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Domcke W, Sobolewski AL, Schlenker CW. Photooxidation of water with heptazine-based molecular photocatalysts: Insights from spectroscopy and computational chemistry. J Chem Phys 2020; 153:100902. [PMID: 32933269 DOI: 10.1063/5.0019984] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We present a conspectus of recent joint spectroscopic and computational studies that provided novel insight into the photochemistry of hydrogen-bonded complexes of the heptazine (Hz) chromophore with hydroxylic substrate molecules (water and phenol). It was found that a functionalized derivative of Hz, tri-anisole-heptazine (TAHz), can photooxidize water and phenol in a homogeneous photochemical reaction. This allows the exploration of the basic mechanisms of the proton-coupled electron-transfer (PCET) process involved in the water photooxidation reaction in well-defined complexes of chemically tunable molecular chromophores with chemically tunable substrate molecules. The unique properties of the excited electronic states of the Hz molecule and derivatives thereof are highlighted. The potential energy landscape relevant for the PCET reaction has been characterized by judicious computational studies. These data provided the basis for the demonstration of rational laser control of PCET reactions in TAHz-phenol complexes by pump-push-probe spectroscopy, which sheds light on the branching mechanisms occurring by the interaction of nonreactive locally excited states of the chromophore with reactive intermolecular charge-transfer states. Extrapolating from these results, we propose a general scenario that unravels the complex photoinduced water-splitting reaction into simple sequential light-driven one-electron redox reactions followed by simple dark radical-radical recombination reactions.
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Affiliation(s)
- Wolfgang Domcke
- Department of Chemistry, Technical University of Munich, D-85747 Garching, Germany
| | | | - Cody W Schlenker
- Department of Chemistry, University of Washington, Seattle, Washington 98195, USA
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20
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Jiang Y, Liu YY, Liu X, Lin H, Gao K, Lai WY, Huang W. Organic solid-state lasers: a materials view and future development. Chem Soc Rev 2020; 49:5885-5944. [PMID: 32672260 DOI: 10.1039/d0cs00037j] [Citation(s) in RCA: 98] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Lasing applications have spread over various aspects of human life. To meet the developing trends of the laser industry towards being miniature, portable, and highly integrated, new laser technologies are in urgent demand. Organic semiconductors are promising gain medium candidates for novel laser devices, due to their convenient processing techniques, ease of spectral and chemical tuning, low refractive indexes, mechanical flexibilities, and low thresholds, etc. organic solid-state lasers (OSSLs) open up a new horizon of simple, low-cost, time-saving, versatile and environmental-friendly manufacturing technologies for new and desirable laser structures (micro-, asymmetric, flexible, etc.) to unleash the full potential of semiconductor lasers for future electronics. Besides the development of optical feedback structures, the design and synthesis of robust organic gain media is critical as a vigorous aspect of OSSLs. Herein, we provide a comprehensive review of recent advances in organic gain materials, mainly focused on organic semiconductors for OSSLs. The significant breakthroughs toward electrical pumping of OSSLs are emphasized. Opportunities, challenges and future research directions for the design of organic gain media are also discussed.
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Affiliation(s)
- Yi Jiang
- Key Laboratory for Organic Electronics and Information Displays (KLOEID), Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing 210023, China.
| | - Yuan-Yuan Liu
- Key Laboratory for Organic Electronics and Information Displays (KLOEID), Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing 210023, China.
| | - Xu Liu
- Key Laboratory for Organic Electronics and Information Displays (KLOEID), Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing 210023, China.
| | - He Lin
- Key Laboratory for Organic Electronics and Information Displays (KLOEID), Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing 210023, China.
| | - Kun Gao
- Key Laboratory for Organic Electronics and Information Displays (KLOEID), Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing 210023, China.
| | - Wen-Yong Lai
- Key Laboratory for Organic Electronics and Information Displays (KLOEID), Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing 210023, China. and Frontiers Science Center for Flexible Electronics, Xi'an Institute of Flexible Electronics (IFE) and Xi'an Institute of Biomedical Materials & Engineering, Northwestern Polytechnical University, 127 West Youyi Road, Xi'an 710072, China
| | - Wei Huang
- Key Laboratory for Organic Electronics and Information Displays (KLOEID), Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing 210023, China. and Frontiers Science Center for Flexible Electronics, Xi'an Institute of Flexible Electronics (IFE) and Xi'an Institute of Biomedical Materials & Engineering, Northwestern Polytechnical University, 127 West Youyi Road, Xi'an 710072, China
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21
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Montanaro A, Giusti F, Colja M, Brajnik G, Marciniak AMA, Sergo R, De Angelis D, Glerean F, Sparapassi G, Jarc G, Carrato S, Cautero G, Fausti D. Visible pump-mid infrared pump-broadband probe: Development and characterization of a three-pulse setup for single-shot ultrafast spectroscopy at 50 kHz. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2020; 91:073106. [PMID: 32752873 DOI: 10.1063/5.0016362] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 06/22/2020] [Indexed: 06/11/2023]
Abstract
We report here an experimental setup to perform three-pulse pump-probe measurements over a wide wavelength and temperature range. By combining two pump pulses in the visible (650 nm-900 nm) and mid-IR (5 μm-20 μm) range, with a broadband supercontinuum white-light probe, our apparatus enables both the combined selective excitation of different material degrees of freedom and a full time-dependent reconstruction of the non-equilibrium dielectric function of the sample. We describe here the optical setup, the cryogenic sample environment, and the custom-made acquisition electronics capable of referenced single-pulse detection of broadband spectra at the maximum repetition rate of 50 kHz, achieving a sensitivity of the order of 10-4 over an integration time of 1 s. We demonstrate the performance of the setup by reporting data on a mid-IR pump, optical push, and broadband probe in a single crystal of Bi2Sr2Y0.08Ca0.92Cu2O8+δ across the superconducting and pseudogap phases.
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Affiliation(s)
- Angela Montanaro
- Department of Physics, Università degli Studi di Trieste, 34127 Trieste, Italy
| | - Francesca Giusti
- Department of Physics, Università degli Studi di Trieste, 34127 Trieste, Italy
| | - Matija Colja
- Elettra Sincrotrone Trieste S.C.p.A., 34127 Basovizza Trieste, Italy
| | - Gabriele Brajnik
- Elettra Sincrotrone Trieste S.C.p.A., 34127 Basovizza Trieste, Italy
| | | | - Rudi Sergo
- Elettra Sincrotrone Trieste S.C.p.A., 34127 Basovizza Trieste, Italy
| | - Dario De Angelis
- Elettra Sincrotrone Trieste S.C.p.A., 34127 Basovizza Trieste, Italy
| | - Filippo Glerean
- Department of Physics, Università degli Studi di Trieste, 34127 Trieste, Italy
| | - Giorgia Sparapassi
- Department of Physics, Università degli Studi di Trieste, 34127 Trieste, Italy
| | - Giacomo Jarc
- Department of Physics, Università degli Studi di Trieste, 34127 Trieste, Italy
| | - Sergio Carrato
- Department of Engineering and Architecture, Università degli Studi di Trieste, 34127 Trieste, Italy
| | - Giuseppe Cautero
- Elettra Sincrotrone Trieste S.C.p.A., 34127 Basovizza Trieste, Italy
| | - Daniele Fausti
- Department of Physics, Università degli Studi di Trieste, 34127 Trieste, Italy
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22
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Eng J, Penfold TJ. Understanding and Designing Thermally Activated Delayed Fluorescence Emitters: Beyond the Energy Gap Approximation. CHEM REC 2020; 20:831-856. [PMID: 32267093 DOI: 10.1002/tcr.202000013] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 03/13/2020] [Indexed: 11/08/2022]
Abstract
In this article recent progress in the development of molecules exhibiting Thermally Activated Delayed Fluorescence (TADF) is discussed with a particular focus upon their application as emitters in highly efficient organic light emitting diodes (OLEDs). The key aspects controlling the desirable functional properties, e. g. fast intersystem crossing, high radiative rate and unity quantum yield, are introduced with a particular focus upon the competition between the key requirements needed to achieve high performance OLEDs. The design rules required for organic and metal organic materials are discussed, and the correlation between them outlined. Recent progress towards understanding the influence of the interaction between a molecule and its environment are explained as is the role of the mechanism for excited state formation in OLEDs. Finally, all of these aspects are combined to discuss the ability to implement high level design rules for achieving higher quality materials for commercial applications. This article highlights the significant progress that has been made in recent years, but also outlines the significant challenges which persist to achieve a full understanding of the TADF mechanism and improve the stability and performance of these materials.
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Affiliation(s)
- Julien Eng
- Chemistry, School of Natural and Environmental Sciences, Newcastle University, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK
| | - Thomas J Penfold
- Chemistry, School of Natural and Environmental Sciences, Newcastle University, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK
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23
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Gao Y, Nie W, Wang X, Fan F, Li C. Advanced space- and time-resolved techniques for photocatalyst studies. Chem Commun (Camb) 2020; 56:1007-1021. [DOI: 10.1039/c9cc07128h] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Nanoparticle photocatalysts present the obvious characteristic of heterogeneity in structure, energy, and function at spatial and temporal scales.
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Affiliation(s)
- Yuying Gao
- State Key Laboratory of Catalysis
- Dalian National Laboratory for Clean Energy
- The Collaborative Innovation Centre of Chemistry for Energy Materials (iChEM)
- Dalian Institute of Chemical Physics
- Chinese Academy of Sciences
| | - Wei Nie
- State Key Laboratory of Catalysis
- Dalian National Laboratory for Clean Energy
- The Collaborative Innovation Centre of Chemistry for Energy Materials (iChEM)
- Dalian Institute of Chemical Physics
- Chinese Academy of Sciences
| | - Xiuli Wang
- State Key Laboratory of Catalysis
- Dalian National Laboratory for Clean Energy
- The Collaborative Innovation Centre of Chemistry for Energy Materials (iChEM)
- Dalian Institute of Chemical Physics
- Chinese Academy of Sciences
| | - Fengtao Fan
- State Key Laboratory of Catalysis
- Dalian National Laboratory for Clean Energy
- The Collaborative Innovation Centre of Chemistry for Energy Materials (iChEM)
- Dalian Institute of Chemical Physics
- Chinese Academy of Sciences
| | - Can Li
- State Key Laboratory of Catalysis
- Dalian National Laboratory for Clean Energy
- The Collaborative Innovation Centre of Chemistry for Energy Materials (iChEM)
- Dalian Institute of Chemical Physics
- Chinese Academy of Sciences
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24
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Zhou X, Zhao M, Zhou J, Liu L, Ma Y. Polarized Species in an Organic Semiconductor Laser. J Phys Chem Lett 2019; 10:7905-7909. [PMID: 31786918 DOI: 10.1021/acs.jpclett.9b03198] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Meeting the challenge of direct electrically driven organic semiconductor lasers (OSLs), the design of OSL materials is being studied. Polarized species generally exist in conjugated organic materials and play an important role in the photophysics procedure; therefore, understanding these species is beneficial for designing novel OSL materials. Here, we use the amplified spontaneous emission effect as a medium to reveal a carbazole-benzothiadiazole-based polarized species induced by a charge transfer process. Spectroscopic analysis confirms that this polarized species that acted as a CT pair defect has a negative influence on the ASE stability and solid state fluorescent quantum yield. This inspires us to be cautious in terms of some specific molecular group combinations when designing OSL materials.
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Affiliation(s)
- Xuehong Zhou
- Institute of Polymer Optoelectronic Materials & Devices, State Key Laboratory of Luminescent Materials & Devices , South China University of Technology , Guangzhou 510640 , P. R. China
| | - Manlin Zhao
- Institute of Polymer Optoelectronic Materials & Devices, State Key Laboratory of Luminescent Materials & Devices , South China University of Technology , Guangzhou 510640 , P. R. China
| | - Jiadong Zhou
- Institute of Polymer Optoelectronic Materials & Devices, State Key Laboratory of Luminescent Materials & Devices , South China University of Technology , Guangzhou 510640 , P. R. China
| | - Linlin Liu
- Institute of Polymer Optoelectronic Materials & Devices, State Key Laboratory of Luminescent Materials & Devices , South China University of Technology , Guangzhou 510640 , P. R. China
| | - Yuguang Ma
- Institute of Polymer Optoelectronic Materials & Devices, State Key Laboratory of Luminescent Materials & Devices , South China University of Technology , Guangzhou 510640 , P. R. China
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25
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Alvertis AM, Schröder FAYN, Chin AW. Non-equilibrium relaxation of hot states in organic semiconductors: Impact of mode-selective excitation on charge transfer. J Chem Phys 2019; 151:084104. [PMID: 31470711 DOI: 10.1063/1.5115239] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The theoretical study of open quantum systems strongly coupled to a vibrational environment remains computationally challenging due to the strongly non-Markovian characteristics of the dynamics. We study this problem in the case of a molecular dimer of the organic semiconductor tetracene, the exciton states of which are strongly coupled to a few hundreds of molecular vibrations. To do so, we employ a previously developed tensor network approach, based on the formalism of matrix product states. By analyzing the entanglement structure of the system wavefunction, we can expand it in a tree tensor network state, which allows us to perform a fully quantum mechanical time evolution of the exciton-vibrational system, including the effect of 156 molecular vibrations. We simulate the dynamics of hot states, i.e., states resulting from excess energy photoexcitation, by constructing various initial bath states, and show that the exciton system indeed has a memory of those initial configurations. In particular, the specific pathway of vibrational relaxation is shown to strongly affect the quantum coherence between exciton states in time scales relevant for the ultrafast dynamics of application-relevant processes such as charge transfer. The preferential excitation of low-frequency modes leads to a limited number of relaxation pathways, thus "protecting" quantum coherence and leading to a significant increase in the charge transfer yield in the dimer structure.
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Affiliation(s)
- Antonios M Alvertis
- Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Florian A Y N Schröder
- Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Alex W Chin
- CNRS, Institut des NanoSciences de Paris, Sorbonne Université, 4 place Jussieu boite courrier 840, 75252 Paris Cedex 05, France
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26
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Kinyua DM, Long H, Xing X, Njoroge S, Wang K, Wang B, Lu P. Gigahertz acoustic vibrations of Ga-doped ZnO nanoparticle array. NANOTECHNOLOGY 2019; 30:305201. [PMID: 30959488 DOI: 10.1088/1361-6528/ab1739] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
In this work, we present an experimental study on the acoustic vibrations of ZnO nanoparticles array with different concentration of Ga dopings by using femtosecond pump-probe technique. The Ga-doped ZnO (GZO) nano-triangle particles with the sizes of 190, 232 and 348 nm are fabricated by nanosphere lithography and pulsed laser deposition method. The result indicates that the frequency of acoustic vibrations of GZO nanoparticles decrease as the Ga-concentration is increased. Importantly, the vibration period of the GZO nanoparticles at the same Ga doping concentration show a nonlinear increase as the nanoparticle size is increased, which is different from the common linear dependency in undoped ZnO nanoparticles. It may be attributed to the crystal structure distortion and elastic characteristics variation due to Ga doping, and the elastic modulus at 7.3% Ga doping is decreased by 30%-60% for GZO nanoparticles with different sizes. The study can be very helpful for evaluating the crystal structure distortion and elastic characteristics of doped nano-materials with optical methods. Besides, it can offer a complementary method of thermal management in ZnO based optoelectronic devices.
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Affiliation(s)
- Dickson Mwenda Kinyua
- Wuhan National Laboratory for Optoelectronics (WNLO) and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, People's Republic of China
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27
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Block A, Liebel M, Yu R, Spector M, Sivan Y, García de Abajo FJ, van Hulst NF. Tracking ultrafast hot-electron diffusion in space and time by ultrafast thermomodulation microscopy. SCIENCE ADVANCES 2019; 5:eaav8965. [PMID: 31093529 PMCID: PMC6510559 DOI: 10.1126/sciadv.aav8965] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 03/21/2019] [Indexed: 05/24/2023]
Abstract
The ultrafast response of metals to light is governed by intriguing nonequilibrium dynamics involving the interplay of excited electrons and phonons. The coupling between them leads to nonlinear diffusion behavior on ultrashort time scales. Here, we use scanning ultrafast thermomodulation microscopy to image the spatiotemporal hot-electron diffusion in thin gold films. By tracking local transient reflectivity with 20-nm spatial precision and 0.25-ps temporal resolution, we reveal two distinct diffusion regimes: an initial rapid diffusion during the first few picoseconds, followed by about 100-fold slower diffusion at longer times. We find a slower initial diffusion than previously predicted for purely electronic diffusion. We develop a comprehensive three-dimensional model based on a two-temperature model and evaluation of the thermo-optical response, taking into account the delaying effect of electron-phonon coupling. Our simulations describe well the observed diffusion dynamics and let us identify the two diffusion regimes as hot-electron and phonon-limited thermal diffusion, respectively.
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Affiliation(s)
- A. Block
- ICFO–Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels (Barcelona), Spain
| | - M. Liebel
- ICFO–Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels (Barcelona), Spain
| | - R. Yu
- ICFO–Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels (Barcelona), Spain
| | - M. Spector
- Department of Physics, Ben-Gurion University of the Negev, 8410501 Be’er Sheva, Israel
| | - Y. Sivan
- Unit of Electrooptics Engineering, Ben-Gurion University of the Negev, 8410501 Be’er Sheva, Israel
| | - F. J. García de Abajo
- ICFO–Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels (Barcelona), Spain
- ICREA–Institució Catalana de Recerca i Estudis Avançats, 08010 Barcelona, Spain
| | - N. F. van Hulst
- ICFO–Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels (Barcelona), Spain
- ICREA–Institució Catalana de Recerca i Estudis Avançats, 08010 Barcelona, Spain
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28
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Yao X, Wang XY, Simpson C, Paternò GM, Guizzardi M, Wagner M, Cerullo G, Scotognella F, Watson MD, Narita A, Müllen K. Regioselective Hydrogenation of a 60-Carbon Nanographene Molecule toward a Circumbiphenyl Core. J Am Chem Soc 2019; 141:4230-4234. [PMID: 30794391 PMCID: PMC6728095 DOI: 10.1021/jacs.9b00384] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
Regioselective peripheral
hydrogenation of a nanographene molecule
with 60 contiguous sp2 carbons provides unprecedented access
to peralkylated circumbiphenyl (1). Conversion to the
circumbiphenyl core structure was unambiguously validated by MALDI-TOF
mass spectrometry, NMR, FT-IR, and Raman spectroscopy. UV–vis
absorption spectra and DFT calculations demonstrated the significant
change of the optoelectronic properties upon peripheral hydrogenation.
Stimulated emission from 1, observed via ultrafast transient
absorption measurements, indicates potential as an optical gain material.
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Affiliation(s)
- Xuelin Yao
- Max Planck Institute for Polymer Research , Ackermannweg 10 , 55128 Mainz , Germany
| | - Xiao-Ye Wang
- Max Planck Institute for Polymer Research , Ackermannweg 10 , 55128 Mainz , Germany
| | - Christopher Simpson
- Max Planck Institute for Polymer Research , Ackermannweg 10 , 55128 Mainz , Germany
| | - Giuseppe M Paternò
- Istituto Italiano di Tecnologia, Center for Nano Science and Technology , 20133 Milano , Italy
| | - Michele Guizzardi
- IFN-CNR, Department of Physics , Politecnico di Milano , 20133 Milano , Italy
| | - Manfred Wagner
- Max Planck Institute for Polymer Research , Ackermannweg 10 , 55128 Mainz , Germany
| | - Giulio Cerullo
- IFN-CNR, Department of Physics , Politecnico di Milano , 20133 Milano , Italy
| | - Francesco Scotognella
- Istituto Italiano di Tecnologia, Center for Nano Science and Technology , 20133 Milano , Italy.,IFN-CNR, Department of Physics , Politecnico di Milano , 20133 Milano , Italy
| | - Mark D Watson
- Department of Chemistry , University of Kentucky , Lexington , Kentucky 40506-0055 , United States
| | - 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 904-0495 , Japan
| | - 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
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29
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de Wergifosse M, Grimme S. Nonlinear-response properties in a simplified time-dependent density functional theory (sTD-DFT) framework: Evaluation of excited-state absorption spectra. J Chem Phys 2019; 150:094112. [DOI: 10.1063/1.5080199] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Affiliation(s)
- Marc de Wergifosse
- Mulliken Center for Theoretical Chemistry, Institut für Physikalische und Theoretische Chemie, Beringstr. 4, 53115 Bonn, Germany
| | - Stefan Grimme
- Mulliken Center for Theoretical Chemistry, Institut für Physikalische und Theoretische Chemie, Beringstr. 4, 53115 Bonn, Germany
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30
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Iimori T, Awasthi K, Chiou CS, Diau EWG, Ohta N. Fluorescence enhancement induced by quadratic electric-field effects on singlet exciton dynamics in poly(3-hexylthiophene) dispersed in poly(methyl methacrylate). Phys Chem Chem Phys 2019; 21:5695-5704. [PMID: 30801107 DOI: 10.1039/c8cp07801g] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The dynamics of the exciton generated by photoexcitation of a regioregular poly(3-hexylthiophene) (P3HT) polymer dispersed in a poly(methyl methacrylate) (PMMA) matrix was examined using electro-photoluminescence (E-PL) spectroscopy, where electric field effects on the photoluminescence (PL) spectra were measured. The quadratic electric-field effect was investigated using the modulation technique, with field-induced changes in the PL intensity monitored at the second harmonic of the modulation frequency of the applied electric field. Absorption and PL spectra indicated the formation of both ordered crystalline aggregates and amorphous regions of P3HT polymer chains. Although previous studies of electric field effects on π-conjugated polymers have generally shown that the PL intensity is decreased by electric fields, we report that the PL intensity of P3HT and PL lifetime increased with the quadratic electric-field effect. The magnitude of the change in PL intensity was quantitatively explained in terms of the field-induced decrease in the nonradiative decay rate constants of the exciton. We proposed that a delayed PL, originating from charge carrier recombination, was enhanced in the presence of electric fields. The rate constant of the downhill relaxation process of the exciton, which originated from the relaxation in distributed energy levels due to an inherent energetic disorder in P3HT aggregates, was implied to decrease in the presence of electric fields. The radiative decay rate constant and PL quantum yield of P3HT dissolved in solution, which were evaluated from the molar extinction coefficient and the PL lifetime, were compared with those of P3HT dispersed in a PMMA matrix.
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Affiliation(s)
- Toshifumi Iimori
- Department of Applied Chemistry, Muroran Institute of Technology, Mizumoto-cho, Muroran 050-8585, Japan
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31
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Beane G, Devkota T, Brown BS, Hartland GV. Ultrafast measurements of the dynamics of single nanostructures: a review. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2019; 82:016401. [PMID: 30485256 DOI: 10.1088/1361-6633/aaea4b] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The ability to study single particles has revolutionized nanoscience. The advantage of single particle spectroscopy measurements compared to conventional ensemble studies is that they remove averaging effects from the different sizes and shapes that are present in the samples. In time-resolved experiments this is important for unraveling homogeneous and inhomogeneous broadening effects in lifetime measurements. In this report, recent progress in the development of ultrafast time-resolved spectroscopic techniques for interrogating single nanostructures will be discussed. The techniques include far-field experiments that utilize high numerical aperture (NA) microscope objectives, near-field scanning optical microscopy (NSOM) measurements, ultrafast electron microscopy (UEM), and time-resolved x-ray diffraction experiments. Examples will be given of the application of these techniques to studying energy relaxation processes in nanoparticles, and the motion of plasmons, excitons and/or charge carriers in different types of nanostructures.
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Affiliation(s)
- Gary Beane
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, United States of America
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32
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Liu Y, Gao Z, Tan Y, Chen F. Enhancement of Out-of-Plane Charge Transport in a Vertically Stacked Two-Dimensional Heterostructure Using Point Defects. ACS NANO 2018; 12:10529-10536. [PMID: 30230812 DOI: 10.1021/acsnano.8b06503] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Point defects in 2D materials block in-plane charge transport, which incurs negative effects on the photoresponse of 2D monolayer materials. In contrast to in-plane charge transport, we show that out-of-plane charge transport in 2D materials can be enhanced through controllable formation of point defects, thus enhancing the photoresponse of a vertical heterostructure. Graphene and WSe2 monolayers were stacked together to construct a vertical heterostructure (W/G). Se point defects were artificially formed on the top atomic layer of WSe2 with controllable density via Ga ion irradiation. The interlayer charge transport in the W/G heterostructure was detected with femtosecond optical probe-pump measurements and photoelectric detection. Our experiments show that point defects can be used to provide higher transfer rate for out-of-plane charge transport and more electronic states for photoexcitation, leading to enhanced photoinduced interlayer charge transfer from WSe2 to graphene. Based on this feature, a photodetector based on W/G modified by point defects is proposed and implemented, exhibiting a fast photoresponsivity (∼0.6 ms) (2 orders of magnitude larger than the photoresponse in pristine W/G). This work demonstrates that out-of-plane charge transport is enhanced by the presence of point defects and illustrates an efficient method to optimize the performance of photoelectric devices based on vertical heterostructures.
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Affiliation(s)
- Yanran Liu
- School of Physics, State Key Laboratory of Crystal Materials , Shandong University , Jinan , Shandong 250100 , China
| | | | - Yang Tan
- School of Physics, State Key Laboratory of Crystal Materials , Shandong University , Jinan , Shandong 250100 , China
| | - Feng Chen
- School of Physics, State Key Laboratory of Crystal Materials , Shandong University , Jinan , Shandong 250100 , China
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33
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Lang B. Photometrics of ultrafast and fast broadband electronic transient absorption spectroscopy: State of the art. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:093112. [PMID: 30278696 DOI: 10.1063/1.5039457] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 08/30/2018] [Indexed: 06/08/2023]
Abstract
The physical limits of the photometric resolution in broadband electronic transient absorption spectroscopy are discussed together with solutions for how to reach these limits in practice. In the first part, quantitative expressions for the noise contributions to the transient absorption signal are derived and experimentally tested. Experimental approaches described in the literature are discussed and compared on this basis. Guide-lines for designing a setup are established. In the second part, a method for obtaining nearly shot-noise limited kinetics with photometric resolution of the order of 100 μOD in overall measurement times of a few minutes from femtosecond to microsecond time scale is presented. The results are discussed in view of other experiments of step-scan type which are subject to a background or to correlated noise. Finally, detailed information is provided on how to obtain transient absorption spectra where counting statistics are the sole source of noise. A method for how to suppress outliers without introducing bias is discussed. An application example is given to demonstrate the achievable signal-to-noise level and the fast acquisition time.
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Affiliation(s)
- Bernhard Lang
- Department of Physical Chemistry, University of Geneva, 30 Quai Ernest Ansermet, CH-1211 Genève 4, Switzerland
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34
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Causa' M, Ramirez I, Martinez Hardigree JF, Riede M, Banerji N. Femtosecond Dynamics of Photoexcited C 60 Films. J Phys Chem Lett 2018; 9:1885-1892. [PMID: 29569924 DOI: 10.1021/acs.jpclett.8b00520] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The well known organic semiconductor C60 is attracting renewed attention due to its centimeter-long electron diffusion length and high performance of solar cells containing 95% fullerene, yet its photophysical properties remain poorly understood. We elucidate the dynamics of Frenkel and intermolecular (inter-C60) charge-transfer (CT) excitons in neat and diluted C60 films from high-quality femtosecond transient absorption (TA) measurements performed at low fluences and free from oxygen or pump-induced photodimerization. We find from preferential excitation of either species that the CT excitons give rise to a strong electro-absorption (EA) signal but are extremely short-lived. The Frenkel exciton relaxation and triplet yield strongly depend on the C60 aggregation. Finally, TA measurements on full devices with applied electric field allow us to optically monitor the dissociation of CT excitons into free charges for the first time and to demonstrate the influence of cluster size on the spectral signature of the C60 anion.
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Affiliation(s)
- Martina Causa'
- Department of Chemistry and Biochemistry , University of Bern , Freiestrasse 3 , 3012 Bern , Switzerland
| | - Ivan Ramirez
- Clarendon Laboratory, Department of Physics , University of Oxford , Parks Road , OX1 3PU , Oxford , United Kingdom
| | - Josue F Martinez Hardigree
- Clarendon Laboratory, Department of Physics , University of Oxford , Parks Road , OX1 3PU , Oxford , United Kingdom
| | - Moritz Riede
- Clarendon Laboratory, Department of Physics , University of Oxford , Parks Road , OX1 3PU , Oxford , United Kingdom
| | - Natalie Banerji
- Department of Chemistry and Biochemistry , University of Bern , Freiestrasse 3 , 3012 Bern , Switzerland
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35
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Goetz S, Li D, Kolb V, Pflaum J, Brixner T. Coherent two-dimensional fluorescence micro-spectroscopy. OPTICS EXPRESS 2018; 26:3915-3925. [PMID: 29475248 DOI: 10.1364/oe.26.003915] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 01/02/2018] [Indexed: 05/22/2023]
Abstract
We have developed coherent two-dimensional (2D) fluorescence micro-spectroscopy which probes the nonlinear optical response at surfaces via fluorescence detection with sub-micron spatial resolution. This enables the investigation of microscopic variations in heterogeneous systems. An LCD-based pulse shaper in 4f geometry is used to create collinear trains of 12-fs visible/NIR laser pulses in the focus of an NA = 1.4 immersion-oil microscope objective. We demonstrate the capabilities of the new method by presenting 2D spectra, analyzed via phase cycling, as a function of position of selected sub-micron regions from a laterally nanostructured polycrystalline thin film of fluorinated zinc phthalocyanine (F16ZnPc).
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36
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Oliveira EF, Shi J, Lavarda FC, Lüer L, Milián-Medina B, Gierschner J. Excited state absorption spectra of dissolved and aggregated distyrylbenzene: A TD-DFT state and vibronic analysis. J Chem Phys 2017; 147:034903. [DOI: 10.1063/1.4993216] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Eliezer Fernando Oliveira
- UNESP–Universidade Estadual Paulista, POSMAT–Graduate Program in Material Science and Technology, Av. Eng. Luiz Edmundo Carrijo Coube 14-01, 17033-360 Bauru, SP, Brazil
| | - Junqing Shi
- Institute for Advanced Studies, IMDEA Nanoscience, C/ Faraday 9, Campus Cantoblanco, 28049 Madrid, Spain
| | - Francisco Carlos Lavarda
- UNESP–Universidade Estadual Paulista, POSMAT–Graduate Program in Material Science and Technology, Av. Eng. Luiz Edmundo Carrijo Coube 14-01, 17033-360 Bauru, SP, Brazil
- DF-FC, UNESP–Universidade Estadual Paulista, Av. Eng. Luiz Edmundo Carrijo Coube 14-01, 17033-360 Bauru, SP, Brazil
| | - Larry Lüer
- Institute for Advanced Studies, IMDEA Nanoscience, C/ Faraday 9, Campus Cantoblanco, 28049 Madrid, Spain
| | - Begoña Milián-Medina
- Institute for Advanced Studies, IMDEA Nanoscience, C/ Faraday 9, Campus Cantoblanco, 28049 Madrid, Spain
- Department for Physical Chemistry, Faculty of Chemistry, University of Valencia, Avenida Dr. Moliner 50, 46100 Burjassot, Valencia, Spain
| | - Johannes Gierschner
- Institute for Advanced Studies, IMDEA Nanoscience, C/ Faraday 9, Campus Cantoblanco, 28049 Madrid, Spain
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37
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Paternò GM, Chen Q, Wang XY, Liu J, Motti SG, Petrozza A, Feng X, Lanzani G, Müllen K, Narita A, Scotognella F. Synthesis of Dibenzo[hi,st
]ovalene and Its Amplified Spontaneous Emission in a Polystyrene Matrix. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201700730] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Giuseppe M. Paternò
- Center for Nano Science and Technology; Istituto Italiano di Tecnologia; 20133 Milano Italy
| | - Qiang Chen
- Max Planck Institute for Polymer Research; 55128 Mainz Germany
| | - Xiao-Ye Wang
- Max Planck Institute for Polymer Research; 55128 Mainz Germany
| | - Junzhi Liu
- Technische Universität Dresden; Center for Advancing Electronics Dresden & Department of Chemistry and Food Chemistry; 01062 Dresden Germany
| | - Silvia G. Motti
- Center for Nano Science and Technology; Istituto Italiano di Tecnologia; 20133 Milano Italy
| | - Annamaria Petrozza
- Center for Nano Science and Technology; Istituto Italiano di Tecnologia; 20133 Milano Italy
| | - Xinliang Feng
- Technische Universität Dresden; Center for Advancing Electronics Dresden & Department of Chemistry and Food Chemistry; 01062 Dresden Germany
| | - Guglielmo Lanzani
- Center for Nano Science and Technology; Istituto Italiano di Tecnologia; 20133 Milano Italy
- Politecnico di Milano; Department of Physics; 20133 Milano Italy
| | - Klaus Müllen
- Max Planck Institute for Polymer Research; 55128 Mainz Germany
| | - Akimitsu Narita
- Max Planck Institute for Polymer Research; 55128 Mainz Germany
| | - Francesco Scotognella
- Center for Nano Science and Technology; Istituto Italiano di Tecnologia; 20133 Milano Italy
- Politecnico di Milano; Department of Physics; 20133 Milano Italy
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38
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Paternò GM, Chen Q, Wang XY, Liu J, Motti SG, Petrozza A, Feng X, Lanzani G, Müllen K, Narita A, Scotognella F. Synthesis of Dibenzo[hi,st]ovalene and Its Amplified Spontaneous Emission in a Polystyrene Matrix. Angew Chem Int Ed Engl 2017; 56:6753-6757. [PMID: 28493640 DOI: 10.1002/anie.201700730] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Indexed: 11/06/2022]
Abstract
A large number of graphene molecules, or large polycyclic aromatic hydrocarbons (PAHs), have been synthesized and display various optoelectronic properties. Nevertheless, their potential for application in photonics has remained largely unexplored. Herein, we describe the synthesis of a highly luminescent and stable graphene molecule, namely a substituted dibenzo[hi,st]ovalene (DBO 1), with zigzag edges and elucidate its promising optical-gain properties by means of ultrafast transient absorption spectroscopy. Upon incorporation of DBO into an inert polystyrene matrix, amplified stimulated emission can be observed with a relatively low power threshold (ca. 60 μJ cm-2 ), thus highlighting its high potential for lasing applications.
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Affiliation(s)
- Giuseppe M Paternò
- Center for Nano Science and Technology, Istituto Italiano di Tecnologia, 20133, Milano, Italy
| | - Qiang Chen
- Max Planck Institute for Polymer Research, 55128, Mainz, Germany
| | - Xiao-Ye Wang
- Max Planck Institute for Polymer Research, 55128, Mainz, Germany
| | - Junzhi Liu
- Technische Universität Dresden, Center for Advancing Electronics Dresden & Department of Chemistry and Food Chemistry, 01062, Dresden, Germany
| | - Silvia G Motti
- Center for Nano Science and Technology, Istituto Italiano di Tecnologia, 20133, Milano, Italy
| | - Annamaria Petrozza
- Center for Nano Science and Technology, Istituto Italiano di Tecnologia, 20133, Milano, Italy
| | - Xinliang Feng
- Technische Universität Dresden, Center for Advancing Electronics Dresden & Department of Chemistry and Food Chemistry, 01062, Dresden, Germany
| | - Guglielmo Lanzani
- Center for Nano Science and Technology, Istituto Italiano di Tecnologia, 20133, Milano, Italy.,Politecnico di Milano, Department of Physics, 20133, Milano, Italy
| | - Klaus Müllen
- Max Planck Institute for Polymer Research, 55128, Mainz, Germany
| | - Akimitsu Narita
- Max Planck Institute for Polymer Research, 55128, Mainz, Germany
| | - Francesco Scotognella
- Center for Nano Science and Technology, Istituto Italiano di Tecnologia, 20133, Milano, Italy.,Politecnico di Milano, Department of Physics, 20133, Milano, Italy
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39
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Jakowetz AC, Böhm ML, Sadhanala A, Huettner S, Rao A, Friend RH. Visualizing excitations at buried heterojunctions in organic semiconductor blends. NATURE MATERIALS 2017; 16:551-557. [PMID: 28218921 DOI: 10.1038/nmat4865] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 01/19/2017] [Indexed: 05/28/2023]
Abstract
Interfaces play a crucial role in semiconductor devices, but in many device architectures they are nanostructured, disordered and buried away from the surface of the sample. Conventional optical, X-ray and photoelectron probes often fail to provide interface-specific information in such systems. Here we develop an all-optical time-resolved method to probe the local energetic landscape and electronic dynamics at such interfaces, based on the Stark effect caused by electron-hole pairs photo-generated across the interface. Using this method, we found that the electronically active sites at the polymer/fullerene interfaces in model bulk-heterojunction blends fall within the low-energy tail of the absorption spectrum. This suggests that these sites are highly ordered compared with the bulk of the polymer film, leading to large wavefunction delocalization and low site energies. We also detected a 100 fs migration of holes from higher- to lower-energy sites, consistent with these charges moving ballistically into more ordered polymer regions. This ultrafast charge motion may be key to separating electron-hole pairs into free charges against the Coulomb interaction.
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Affiliation(s)
- Andreas C Jakowetz
- Cavendish Laboratory, Department of Physics, University of Cambridge, J J Thomson Avenue, Cambridge CB3 0HE, UK
| | - Marcus L Böhm
- Cavendish Laboratory, Department of Physics, University of Cambridge, J J Thomson Avenue, Cambridge CB3 0HE, UK
| | - Aditya Sadhanala
- Cavendish Laboratory, Department of Physics, University of Cambridge, J J Thomson Avenue, Cambridge CB3 0HE, UK
| | - Sven Huettner
- Fakultät für Biologie, Chemie und Geowissenschaften, University Bayreuth, Universitätsstrasse 30, 95440 Bayreuth, Germany
| | - Akshay Rao
- Cavendish Laboratory, Department of Physics, University of Cambridge, J J Thomson Avenue, Cambridge CB3 0HE, UK
| | - Richard H Friend
- Cavendish Laboratory, Department of Physics, University of Cambridge, J J Thomson Avenue, Cambridge CB3 0HE, UK
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40
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Loukianov A, Niedringhaus A, Berg B, Pan J, Senlik SS, Ogilvie JP. Two-Dimensional Electronic Stark Spectroscopy. J Phys Chem Lett 2017; 8:679-683. [PMID: 28099020 DOI: 10.1021/acs.jpclett.6b02695] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Characterizing ultrafast energy and charge transfer is important for understanding a wide range of systems, from natural photosynthetic complexes to organic photovoltaics. Distinguishing the kinetic processes of energy transfer and charge separation in such systems is challenging due to the lack of clear spectral signatures of charge transfer states, which are typically nonradiative. Stark spectroscopy has proven to be a valuable method for uncovering charge transfer states. Here we extend the dimensionality of Stark spectroscopy to perform two-dimensional electronic Stark spectroscopy. We demonstrate the method on TIPS-pentacene in 3-methylpentane at 77 K. The additional frequency dimension of two-dimensional Stark spectroscopy promises to enable the identification of charge transfer states, their coupling to other charge transfer and exciton states, and their involvement in charge separation processes.
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Affiliation(s)
- Anton Loukianov
- Department of Physics, University of Michigan , 450 Church Street, Ann Arbor, Michigan 48109, United States
| | - Andrew Niedringhaus
- Department of Physics, University of Michigan , 450 Church Street, Ann Arbor, Michigan 48109, United States
| | - Brandon Berg
- Department of Physics, University of Michigan , 450 Church Street, Ann Arbor, Michigan 48109, United States
| | - Jie Pan
- Department of Physics, University of Michigan , 450 Church Street, Ann Arbor, Michigan 48109, United States
| | - S Seckin Senlik
- Department of Physics, University of Michigan , 450 Church Street, Ann Arbor, Michigan 48109, United States
| | - Jennifer P Ogilvie
- Department of Physics, University of Michigan , 450 Church Street, Ann Arbor, Michigan 48109, United States
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41
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Abstract
Organic (opto)electronic materials have received considerable attention due to their applications in thin-film-transistors, light-emitting diodes, solar cells, sensors, photorefractive devices, and many others. The technological promises include low cost of these materials and the possibility of their room-temperature deposition from solution on large-area and/or flexible substrates. The article reviews the current understanding of the physical mechanisms that determine the (opto)electronic properties of high-performance organic materials. The focus of the review is on photoinduced processes and on electronic properties important for optoelectronic applications relying on charge carrier photogeneration. Additionally, it highlights the capabilities of various experimental techniques for characterization of these materials, summarizes top-of-the-line device performance, and outlines recent trends in the further development of the field. The properties of materials based both on small molecules and on conjugated polymers are considered, and their applications in organic solar cells, photodetectors, and photorefractive devices are discussed.
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Affiliation(s)
- Oksana Ostroverkhova
- Department of Physics, Oregon State University , Corvallis, Oregon 97331, United States
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42
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Baudisch M, Wolter B, Pullen M, Hemmer M, Biegert J. High power multi-color OPCPA source with simultaneous femtosecond deep-UV to mid-IR outputs. OPTICS LETTERS 2016; 41:3583-3586. [PMID: 27472624 DOI: 10.1364/ol.41.003583] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Many experimental investigations demand synchronized pulses at various wavelengths, ideally with very short pulse duration and high repetition rate. Here we describe a femtosecond multi-color optical parametric chirped pulse amplifier (OPCPA) with simultaneous outputs from the deep-UV to the mid-IR with optical synchronization. The high repetition rate of 160 kHz is well suited to compensate for low interaction probability or low cross section in strong-field interactions. Our source features high peak powers in the tens to hundreds of MW regime with pulse durations below 110 fs, which is ideal for pump-probe experiments of nonlinear and strong-field physics. We demonstrate its utility by strong-field ionization experiments of xenon in the near- to mid-IR.
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43
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Vega-Mayoral V, Vella D, Borzda T, Prijatelj M, Tempra I, Pogna EAA, Dal Conte S, Topolovsek P, Vujicic N, Cerullo G, Mihailovic D, Gadermaier C. Exciton and charge carrier dynamics in few-layer WS2. NANOSCALE 2016; 8:5428-5434. [PMID: 26890008 DOI: 10.1039/c5nr08384b] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Semiconducting transition metal dichalcogenides (TMDs) have been applied as the active layer in photodetectors and solar cells, displaying substantial charge photogeneration yields. However, their large exciton binding energy, which increases with decreasing thickness (number of layers), as well as the strong resonance peaks in the absorption spectra suggest that excitons are the primary photoexcited states. Detailed time-domain studies of the photoexcitation dynamics in TMDs exist mostly for MoS2. Here, we use femtosecond optical spectroscopy to study the exciton and charge dynamics following impulsive photoexcitation in few-layer WS2. We confirm excitons as the primary photoexcitation species and find that they dissociate into charge pairs with a time constant of about 1.3 ps. The better separation of the spectral features compared to MoS2 allows us to resolve a previously undetected process: these charges diffuse through the samples and get trapped at defects, such as flake edges or grain boundaries, causing an appreciable change of their transient absorption spectra. This finding opens the way to further studies of traps in TMD samples with different defect contents.
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Affiliation(s)
- Victor Vega-Mayoral
- Department of Complex Matter, Jozef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia. and Jozef Stefan International Postgraduate School, Jamova 39, 1000 Ljubljana, Slovenia
| | - Daniele Vella
- Department of Complex Matter, Jozef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia. and Jozef Stefan International Postgraduate School, Jamova 39, 1000 Ljubljana, Slovenia
| | - Tetiana Borzda
- Department of Complex Matter, Jozef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia. and Jozef Stefan International Postgraduate School, Jamova 39, 1000 Ljubljana, Slovenia
| | - Matej Prijatelj
- Department of Complex Matter, Jozef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia. and Jozef Stefan International Postgraduate School, Jamova 39, 1000 Ljubljana, Slovenia
| | - Iacopo Tempra
- IFN-CNR, Department of Physics, Politecnico di Milano, P. Leonardo da Vinci 32, 20133 Milan, Italy
| | - Eva A A Pogna
- IFN-CNR, Department of Physics, Politecnico di Milano, P. Leonardo da Vinci 32, 20133 Milan, Italy
| | - Stefano Dal Conte
- IFN-CNR, Department of Physics, Politecnico di Milano, P. Leonardo da Vinci 32, 20133 Milan, Italy
| | - Peter Topolovsek
- Jozef Stefan International Postgraduate School, Jamova 39, 1000 Ljubljana, Slovenia and Center for Nano Science and Technology, Italian Institute of Technology, Via Pascoli 70/3, 20133 Milano, Italy
| | - Natasa Vujicic
- Institute of Physics, Bijenicka 46, 10000 Zagreb, Croatia and Center of Excellence for Advanced Materials and Sensing Devices, Bijenicka 46, HR-10000, Zagreb, Croatia
| | - Giulio Cerullo
- IFN-CNR, Department of Physics, Politecnico di Milano, P. Leonardo da Vinci 32, 20133 Milan, Italy
| | - Dragan Mihailovic
- Department of Complex Matter, Jozef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia. and Jozef Stefan International Postgraduate School, Jamova 39, 1000 Ljubljana, Slovenia and Center of Excellence in Nanoscience and Nanotechnology, Jamova 39, 1000 Ljubljana, Slovenia
| | - Christoph Gadermaier
- Department of Complex Matter, Jozef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia. and Jozef Stefan International Postgraduate School, Jamova 39, 1000 Ljubljana, Slovenia
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44
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Lu J, Liu H, Tok ES, Sow CH. Interactions between lasers and two-dimensional transition metal dichalcogenides. Chem Soc Rev 2016; 45:2494-515. [DOI: 10.1039/c5cs00553a] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We review the interactions between lasers and TMDs with a focus on the use of laser-based technologies as effective tools for the characterization, modification, and manipulation of TMDs.
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Affiliation(s)
- Junpeng Lu
- Department of Physics
- National University of Singapore
- Singapore 117542
- Singapore
- Center for Advanced 2D materials and Graphene Research Center
| | - Hongwei Liu
- Institute of Materials Research and Engineering
- A*STAR (Agency for Science, Technology and Research)
- Singapore 138634
- Singapore
| | - Eng Soon Tok
- Department of Physics
- National University of Singapore
- Singapore 117542
- Singapore
| | - Chorng-Haur Sow
- Department of Physics
- National University of Singapore
- Singapore 117542
- Singapore
- Center for Advanced 2D materials and Graphene Research Center
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45
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Lambert C, Koch F, Völker SF, Schmiedel A, Holzapfel M, Humeniuk A, Röhr MIS, Mitric R, Brixner T. Energy Transfer Between Squaraine Polymer Sections: From Helix to Zigzag and All the Way Back. J Am Chem Soc 2015; 137:7851-61. [DOI: 10.1021/jacs.5b03644] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Christoph Lambert
- Institut
für Organische Chemie, ‡Center for Nanosystems Chemistry
(CNC), and §Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Federico Koch
- Institut
für Organische Chemie, ‡Center for Nanosystems Chemistry
(CNC), and §Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Sebastian F. Völker
- Institut
für Organische Chemie, ‡Center for Nanosystems Chemistry
(CNC), and §Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Alexander Schmiedel
- Institut
für Organische Chemie, ‡Center for Nanosystems Chemistry
(CNC), and §Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Marco Holzapfel
- Institut
für Organische Chemie, ‡Center for Nanosystems Chemistry
(CNC), and §Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Alexander Humeniuk
- Institut
für Organische Chemie, ‡Center for Nanosystems Chemistry
(CNC), and §Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Merle I. S. Röhr
- Institut
für Organische Chemie, ‡Center for Nanosystems Chemistry
(CNC), and §Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Roland Mitric
- Institut
für Organische Chemie, ‡Center for Nanosystems Chemistry
(CNC), and §Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Tobias Brixner
- Institut
für Organische Chemie, ‡Center for Nanosystems Chemistry
(CNC), and §Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
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46
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Kee TW. Femtosecond Pump-Push-Probe and Pump-Dump-Probe Spectroscopy of Conjugated Polymers: New Insight and Opportunities. J Phys Chem Lett 2014; 5:3231-40. [PMID: 26276338 DOI: 10.1021/jz501549h] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Conjugated polymers are an important class of soft materials that exhibit a wide range of applications. The excited states of conjugated polymers, often referred to as excitons, can either deactivate to yield the ground state or dissociate in the presence of an electron acceptor to form charge carriers. These interesting properties give rise to their luminescence and the photovoltaic effect. Femtosecond spectroscopy is a crucial tool for studying conjugated polymers. Recently, more elaborate experimental configurations utilizing three optical pulses, namely, pump-push-probe and pump-dump-probe, have been employed to investigate the properties of excitons and charge-transfer states of conjugated polymers. These studies have revealed new insight into femtosecond torsional relaxation and detrapping of bound charge pairs of conjugated polymers. This Perspective highlights (1) the recent achievements by several research groups in using pump-push-probe and pump-dump-probe spectroscopy to study conjugated polymers and (2) future opportunities and potential challenges of these techniques.
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Affiliation(s)
- Tak W Kee
- Department of Chemistry, The University of Adelaide, Adelaide, South Australia 5005, Australia
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47
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Abate A, Saliba M, Hollman DJ, Stranks SD, Wojciechowski K, Avolio R, Grancini G, Petrozza A, Snaith HJ. Supramolecular halogen bond passivation of organic-inorganic halide perovskite solar cells. NANO LETTERS 2014; 14:3247-54. [PMID: 24787646 DOI: 10.1021/nl500627x] [Citation(s) in RCA: 256] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Organic-inorganic halide perovskites, such as CH3NH3PbX3 (X = I(-), Br(-), Cl(-)), are attracting growing interest to prepare low-cost solar cells that are capable of converting sunlight to electricity at the highest efficiencies. Despite negligible effort on enhancing materials' purity or passivation of surfaces, high efficiencies have already been achieved. Here, we show that trap states at the perovskite surface generate charge accumulation and consequent recombination losses in working solar cells. We identify that undercoordinated iodine ions within the perovskite structure are responsible and make use of supramolecular halogen bond complexation to successfully passivate these sites. Following this strategy, we demonstrate solar cells with maximum power conversion efficiency of 15.7% and stable power output over 15% under constant 0.81 V forward bias in simulated full sunlight. The surface passivation introduces an important direction for future progress in perovskite solar cells.
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Affiliation(s)
- Antonio Abate
- Clarendon Laboratory, Department of Physics, University of Oxford , Parks Road, Oxford OX1 3PU, United Kingdom
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48
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Amarasinghe Vithanage D, Devižis A, Abramavičius V, Infahsaeng Y, Abramavičius D, MacKenzie RCI, Keivanidis PE, Yartsev A, Hertel D, Nelson J, Sundström V, Gulbinas V. Visualizing charge separation in bulk heterojunction organic solar cells. Nat Commun 2014; 4:2334. [PMID: 23945881 DOI: 10.1038/ncomms3334] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Accepted: 07/22/2013] [Indexed: 11/09/2022] Open
Abstract
Solar cells based on conjugated polymer and fullerene blends have been developed as a low-cost alternative to silicon. For efficient solar cells, electron-hole pairs must separate into free mobile charges that can be extracted in high yield. We still lack good understanding of how, why and when carriers separate against the Coulomb attraction. Here we visualize the charge separation process in bulk heterojunction solar cells by directly measuring charge carrier drift in a polymer:fullerene blend with ultrafast time resolution. We show that initially only closely separated (<1 nm) charge pairs are created and they separate by several nanometres during the first several picoseconds. Charge pairs overcome Coulomb attraction and form free carriers on a subnanosecond time scale. Numerical simulations complementing the experimental data show that fast three-dimensional charge diffusion within an energetically disordered medium, increasing the entropy of the system, is sufficient to drive the charge separation process.
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49
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Koopman WWA, Toffanin S, Natali M, Troisi S, Capelli R, Biondo V, Stefani A, Muccini M. Mapping of charge distribution in organic field-effect transistors by confocal photoluminescence electromodulation microscopy. NANO LETTERS 2014; 14:1695-700. [PMID: 24611682 DOI: 10.1021/nl402603c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
A novel method for mapping the charge density spatial distribution in organic field-effect transistors based on the electromodulation of the photoluminescence is demonstrated. In field-effect transistors exciton quenching is dominated by exciton-charge carrier interaction so that it can be used to map the charge distribution in different operating conditions. From a quantitative analysis of the photoluminescence quenching, the thickness of the charge carrier accumulation layer is derived. The injection of minority charge carriers in unipolar conditions is unexpectedly evidenced, which is not displayed by the electrical characteristics.
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50
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Ultrafast energy transfer in ultrathin organic donor/acceptor blend. Sci Rep 2013; 3:2073. [PMID: 23797845 PMCID: PMC3691563 DOI: 10.1038/srep02073] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 06/07/2013] [Indexed: 02/04/2023] Open
Abstract
It is common knowledge that poly(3-hexylthiophene) (P3HT)/[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) blend, a prototype system for bulk heterojunction (BHJ) solar cells, consists of a network of tens of nanometers-large donor-rich and acceptor-rich phases separated by extended finely intermixed border regions where PCBM diffuse into P3HT. Here we specifically address the photo-induced dynamics in a 10 nm thin P3HT/PCBM blend that consists of the intermixed region only. Using the multi-pass transient absorption technique (TrAMP) that enables us to perform ultra high sensitive measurements, we find that the primary process upon photoexcitation is ultrafast energy transfer from P3HT to PCBM. The expected charge separation due to hole transfer from PCBM to P3HT occurs in the 100 ps timescale. The derived picture is much different from the accepted view of ultra-fast electron transfer at the polymer/PCBM interface and provides new directions for the development of efficient devices.
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