1
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Hoque M, Kamal S, Raghunath S, Foster EJ. Unraveling lignin degradation in fibre cement via multidimensional fluorometry. Sci Rep 2023; 13:8385. [PMID: 37225861 DOI: 10.1038/s41598-023-35560-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 05/20/2023] [Indexed: 05/26/2023] Open
Abstract
Pulp fibre reinforced cement (fibre cement) has the potential to become a forerunner in mitigating the carbon dioxide (CO2) footprint of non-structural materials for residential and commercial structures. However, one of the significant bottlenecks in fibre cement is its poor chemical stability in the alkaline cement matrix. To date, probing the health of pulp fibre in cement is lengthy and laborious, requiring mechanical and chemical separations. In this study, we have demonstrated that it is possible to understand the chemical interactions at the fibre-cement interfaces by tracking lignin in a solid state without using any additional chemicals. For the first time, multidimensional fluorometry is employed for the rapid assessment of the structural change (degradation) of lignin in fibre cement as an indicator of pulp fibre health; providing an excellent platform for the germination of resilient fibre cement with high content of natural lignocellulosic fibre.
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Affiliation(s)
- Mahfuzul Hoque
- Department of Chemical and Biological Engineering, Pulp and Paper Centre, The University of British Columbia, 2385 East Mall, British Columbia, V6T 1Z4, Canada
| | - Saeid Kamal
- Laboratory for Advanced Spectroscopy and Imaging Research (LASIR), Department of Chemistry, The University of British Columbia, 2036 Main Mall, Vancouver, BC, V6T 1Z1, Canada
| | - Sreenath Raghunath
- Department of Chemical and Biological Engineering, Pulp and Paper Centre, The University of British Columbia, 2385 East Mall, British Columbia, V6T 1Z4, Canada
| | - E Johan Foster
- Department of Chemical and Biological Engineering, Pulp and Paper Centre, The University of British Columbia, 2385 East Mall, British Columbia, V6T 1Z4, Canada.
- Bioproducts Institute, 2385 East Mall, Vancouver, BC, V6T 1Z4, Canada.
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2
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Rehhagen C, Rather SR, Schwarz KN, Scholes GD, Lochbrunner S. Comparison of Frenkel and Excimer Exciton Diffusion in Perylene Bisimide Nanoparticles. J Phys Chem Lett 2023; 14:4490-4496. [PMID: 37155571 DOI: 10.1021/acs.jpclett.3c00364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Exciton migration is an important process for light harvesting with organic systems and often the bottleneck. Especially the formation of trap states hinders the mobility considerably. Although excimer excitons are often referred to as traps, their mobility has been demonstrated while their nature is still unclear. Here, we compare the mobility of singlet and excimer excitons in nanoparticles consisting of the same type of perylene bisimide molecules. By changing the preparation conditions, nanoparticles with different intermolecular coupling strengths are prepared. Femtosecond transient absorption spectroscopy reveals the formation of excimer excitons from Frenkel excitons. The mobility of both exciton types is determined by evaluating exciton-exciton annihilation processes. In the lower coupling regime, singlet mobility is observed, whereas for stronger coupling the dynamics is dominated by a 10-fold increased excimer mobility. The excimer mobility can thus even be higher than the singlet mobility and is affected by the intermolecular electronic coupling.
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Affiliation(s)
- Chris Rehhagen
- Institute for Physics and Department Life, Light and Matter, University of Rostock, 18051 Rostock, Germany
| | - Shahnawaz R. Rather
- Frick Laboratory, Princeton University, Princeton, New Jersey 08540, United States
| | - Kyra N Schwarz
- Frick Laboratory, Princeton University, Princeton, New Jersey 08540, United States
| | - Gregory D Scholes
- Frick Laboratory, Princeton University, Princeton, New Jersey 08540, United States
| | - Stefan Lochbrunner
- Institute for Physics and Department Life, Light and Matter, University of Rostock, 18051 Rostock, Germany
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3
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Lowrie W, Westbrook RJE, Guo J, Gonev HI, Marin-Beloqui J, Clarke TM. Organic photovoltaics: The current challenges. J Chem Phys 2023; 158:110901. [PMID: 36948814 DOI: 10.1063/5.0139457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023] Open
Abstract
Organic photovoltaics are remarkably close to reaching a landmark power conversion efficiency of 20%. Given the current urgent concerns regarding climate change, research into renewable energy solutions is crucially important. In this perspective article, we highlight several key aspects of organic photovoltaics, ranging from fundamental understanding to implementation, that need to be addressed to ensure the success of this promising technology. We cover the intriguing ability of some acceptors to undergo efficient charge photogeneration in the absence of an energetic driving force and the effects of the resulting state hybridization. We explore one of the primary loss mechanisms of organic photovoltaics-non-radiative voltage losses-and the influence of the energy gap law. Triplet states are becoming increasingly relevant owing to their presence in even the most efficient non-fullerene blends, and we assess their role as both a loss mechanism and a potential strategy to enhance efficiency. Finally, two ways in which the implementation of organic photovoltaics can be simplified are addressed. The standard bulk heterojunction architecture could be superseded by either single material photovoltaics or sequentially deposited heterojunctions, and the attributes of both are considered. While several important challenges still lie ahead for organic photovoltaics, their future is, indeed, bright.
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Affiliation(s)
- William Lowrie
- Department of Chemistry, University College London, Christopher Ingold Building, London WC1H 0AJ, United Kingdom
| | - Robert J E Westbrook
- Department of Chemistry, University of Washington, Seattle, Washington 98195, USA
| | - Junjun Guo
- Department of Chemistry, University College London, Christopher Ingold Building, London WC1H 0AJ, United Kingdom
| | - Hristo Ivov Gonev
- Department of Chemistry, University College London, Christopher Ingold Building, London WC1H 0AJ, United Kingdom
| | - Jose Marin-Beloqui
- Departamento de Química Física, Universidad de Malaga, Campus Teatinos s/n, 29071 Málaga, Spain
| | - Tracey M Clarke
- Department of Chemistry, University College London, Christopher Ingold Building, London WC1H 0AJ, United Kingdom
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4
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Köse ME. Estimation of Excited-State Geometries of Benzene and Fluorobenzene through Vibronic Analyses of Absorption Spectra. ACS OMEGA 2022; 7:32764-32774. [PMID: 36120020 PMCID: PMC9476181 DOI: 10.1021/acsomega.2c04615] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 08/26/2022] [Indexed: 06/15/2023]
Abstract
The parameters used in theoretical modeling of vibrational patterns within Franck-Condon (FC) approximation can be adjusted to match the vibrationally well-resolved experimental absorption spectrum of molecules. These simulation parameters can then be used to reveal the structural changes occurring between the initial and final states assuming the harmonic oscillator approximation holds for both states. Such a theoretical approach has been applied to benzene and fluorobenzene to disclose the first excited-state geometries of both compounds. The carbon-carbon bond length of benzene in the 1B2u state has been calculated as 1.430 Å, which is in very good agreement with the experimental bond length of 1.432 Å. The FC spectral fit method has been exploited to reveal the 1B2 state of fluorobenzene as well. Commonly employed density functional theory (DFT) and time-dependent DFT methods have been used to calculate the ground- and excited-state geometries of both compounds, respectively. The comparison of geometrical parameters and vibrational frequencies at the relevant states shows that frequently used hybrid functionals perform quite well in the ground state, whereas their performances drop considerably while predicting the excited-state properties. Among the hybrid functionals studied, TD-B3LYP with 6-31+G(d) basis set can be chosen to calculate the excited-state properties of molecules, albeit with much less anticipation of accuracy from the performance that B3LYP usually shows at the ground state.
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5
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Pavliuk MV, Lorenzi M, Morado DR, Gedda L, Wrede S, Mejias SH, Liu A, Senger M, Glover S, Edwards K, Berggren G, Tian H. Polymer Dots as Photoactive Membrane Vesicles for [FeFe]-Hydrogenase Self-Assembly and Solar-Driven Hydrogen Evolution. J Am Chem Soc 2022; 144:13600-13611. [PMID: 35863067 PMCID: PMC9354254 DOI: 10.1021/jacs.2c03882] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
A semiartificial photosynthesis approach that utilizes enzymes for solar fuel production relies on efficient photosensitizers that should match the enzyme activity and enable long-term stability. Polymer dots (Pdots) are biocompatible photosensitizers that are stable at pH 7 and have a readily modifiable surface morphology. Therefore, Pdots can be considered potential photosensitizers to drive such enzyme-based systems for solar fuel formation. This work introduces and unveils in detail the interaction within the biohybrid assembly composed of binary Pdots and the HydA1 [FeFe]-hydrogenase from Chlamydomonas reinhardtii. The direct attachment of hydrogenase on the surface of toroid-shaped Pdots was confirmed by agarose gel electrophoresis, cryogenic transmission electron microscopy (Cryo-TEM), and cryogenic electron tomography (Cryo-ET). Ultrafast transient spectroscopic techniques were used to characterize photoinduced excitation and dissociation into charges within Pdots. The study reveals that implementation of a donor-acceptor architecture for heterojunction Pdots leads to efficient subpicosecond charge separation and thus enhances hydrogen evolution (88 460 μmolH2·gH2ase-1·h-1). Adsorption of [FeFe]-hydrogenase onto Pdots resulted in a stable biohybrid assembly, where hydrogen production persisted for days, reaching a TON of 37 500 ± 1290 in the presence of a redox mediator. This work represents an example of a homogeneous biohybrid system combining polymer nanoparticles and an enzyme. Detailed spectroscopic studies provide a mechanistic understanding of light harvesting, charge separation, and transport studied, which is essential for building semiartificial photosynthetic systems with efficiencies beyond natural and artificial systems.
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Affiliation(s)
- Mariia V Pavliuk
- Department of Chemistry─Ångström Laboratory, Physical Chemistry, Uppsala University, 751 20 Uppsala, Sweden
| | - Marco Lorenzi
- Department of Chemistry─Ångström Laboratory, Molecular Biomimetics, Uppsala University, 751 20 Uppsala, Sweden
| | - Dustin R Morado
- Department of Biochemistry and Biophysics, Science for Life Laboratory, Stockholm University, 171 65 Solna, Sweden
| | - Lars Gedda
- Department of Chemistry─Ångström Laboratory, Physical Chemistry, Uppsala University, 751 20 Uppsala, Sweden
| | - Sina Wrede
- Department of Chemistry─Ångström Laboratory, Physical Chemistry, Uppsala University, 751 20 Uppsala, Sweden
| | - Sara H Mejias
- Department of Chemistry─Ångström Laboratory, Physical Chemistry, Uppsala University, 751 20 Uppsala, Sweden
| | - Aijie Liu
- Department of Chemistry─Ångström Laboratory, Physical Chemistry, Uppsala University, 751 20 Uppsala, Sweden
| | - Moritz Senger
- Department of Chemistry─Ångström Laboratory, Physical Chemistry, Uppsala University, 751 20 Uppsala, Sweden
| | - Starla Glover
- Department of Chemistry─Ångström Laboratory, Physical Chemistry, Uppsala University, 751 20 Uppsala, Sweden
| | - Katarina Edwards
- Department of Chemistry─Ångström Laboratory, Physical Chemistry, Uppsala University, 751 20 Uppsala, Sweden
| | - Gustav Berggren
- Department of Chemistry─Ångström Laboratory, Molecular Biomimetics, Uppsala University, 751 20 Uppsala, Sweden
| | - Haining Tian
- Department of Chemistry─Ångström Laboratory, Physical Chemistry, Uppsala University, 751 20 Uppsala, Sweden
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6
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Rehhagen C, Rather SR, Schwarz KN, Scholes GD, Lochbrunner S. The effect of intermolecular electronic coupling on the exciton dynamics in perylene red nanoparticles. Phys Chem Chem Phys 2022; 24:8695-8704. [PMID: 35373223 DOI: 10.1039/d1cp05375b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Understanding the transport mechanisms of electronic excitations in molecular systems is the basis for their application in light harvesting and opto-electronic devices. The exciton transfer properties depend pivotally on the intermolecular coupling and the latter on the supramolecular structure. In this work, organic nanoparticles of the perylene derivative Perylene Red are prepared with flash-precipitation under different conditions. We correlate their intermolecular couplings, optical spectra, quantum yields, emission lifetimes and their size and characterize their exciton dynamics upon excitation with ultrashort laser pulses by transient absorption spectroscopy. We find that the intermolecular coupling can be varied by changing the preparation conditions and thus the supramolecular structure. In contrast to the monomeric system, the generation of charge-transfer states is found after optical excitation of the nanoparticles. The time of the generation step is in the order of 100 ps and depends on the intermolecular coupling. The mobility of the originally excited excitons is determined from measurements with varying exciton density. To this end, we model the contribution of exciton-exciton annihilation to the exciton decay assuming three-dimensional incoherent diffusion. The extracted exciton diffusion constant of nanoparticles with stronger intermolecular coupling is found to be 0.17 nm2 ps-1 and thereby about ten times higher than in the particles with smaller coupling.
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Affiliation(s)
- Chris Rehhagen
- Institute for Physics and Department of Life, Light and Matter, University of Rostock, 18051 Rostock, Germany.
| | | | - Kyra N Schwarz
- School of Chemistry, University of Melbourne, Parkville, VIC, 3010, Australia
| | | | - Stefan Lochbrunner
- Institute for Physics and Department of Life, Light and Matter, University of Rostock, 18051 Rostock, Germany.
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7
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A polarization scheme that resolves cross-peaks with transient absorption and eliminates diagonal peaks in 2D spectroscopy. Proc Natl Acad Sci U S A 2022; 119:2117398119. [PMID: 35115405 PMCID: PMC8833161 DOI: 10.1073/pnas.2117398119] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/16/2021] [Indexed: 11/18/2022] Open
Abstract
Two-dimensional (2D) optical spectroscopy contains cross-peaks that are helpful features for determining molecular structure and monitoring energy transfer, but they can be difficult to resolve from the much more intense diagonal peaks. Transient absorption (TA) spectra contain transitions similar to cross-peaks in 2D spectroscopy, but in most cases they are obscured by the bleach and stimulated emission peaks. We report a polarization scheme, <0°,0°,+θ2(t2),-θ2(t2)>, that can be easily implemented in the pump-probe beam geometry, used most frequently in 2D and TA spectroscopy. This scheme removes the diagonal peaks in 2D spectroscopies and the intense bleach/stimulated emission peaks in TA spectroscopies, thereby resolving the cross-peak features. At zero pump-probe delay, θ2 = 60° destructively interferes two Feynman paths, eliminating all signals generated by field interactions with four parallel transition dipoles, and the intense diagonal and bleach/stimulated emission peaks. At later delay times, θ2(t2) is adjusted to compensate for anisotropy caused by rotational diffusion. When implemented with TA spectroscopy or microscopy, the pump-probe spectrum is dominated by the cross-peak features. The local oscillator is also attenuated, which enhances the signal two times. This overlooked polarization scheme reduces spectral congestion by eliminating diagonal peaks in 2D spectra and enables TA spectroscopy to measure similar information given by cross-peaks in 2D spectroscopy.
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8
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Nho HW, Park WW, Lee B, Kim S, Yang C, Kwon OH. Intrachain photophysics of a donor-acceptor copolymer. Phys Chem Chem Phys 2021; 24:1982-1992. [PMID: 34897314 DOI: 10.1039/d1cp04093f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
By taking advantage of bulk-heterojunction structures formed by blending conjugated donor polymers and non-fullerene acceptors, organic photovoltaic devices have recently attained promising power conversion efficiencies of above 18%. For optimizing organic photovoltaic devices, it is essential to understand the elementary processes that constitute light harvesters. Utilising femtosecond-resolved spectroscopic techniques that can access the timescales of locally excited (LE) state and charge-transfer (CT)/-separated (CS) states, herein we explored their photophysics in single chains of the top-notch performance donor-acceptor polymer, PM6, which has been widely used as a donor in state-of-the-art non-fullerene organic photovoltaic devices, in a single LE state per chain regime. Our observations revealed the ultrafast formation of a CT state and its equilibrium with the parent LE state. From the chain-length dependence of their lifetimes, the equilibrated states were found to idle until they reach a chain folding. At the chain folding, the CT state transforms into an interchain CT state that bifurcates into forming a CS state or annihilation within a picosecond. The observation of prevalent nonexponential behaviour in the relaxation of the transient species is attributed to the wide chain-length distribution that determines the emergence of the chain foldings in a single chain, thus, the lifetime of a LE and equilibrated CT states. Our findings indicate that the abundance of chain folding, where the generation of the "reactive" CS state is initiated from the interchain CT state, is essential for maximising charge carriers in organic photovoltaic devices based on PM6.
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Affiliation(s)
- Hak-Won Nho
- Department of Chemistry, College of Natural Sciences, Ulsan National Institute of Science and Technology (UNIST), Room 415, Advanced Material Research Building (103), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 44919, Republic of Korea. .,Center for Soft and Living Matter, Institute for Basic Science (IBS), Ulsan 44919, Republic of Korea
| | - Won-Woo Park
- Department of Chemistry, College of Natural Sciences, Ulsan National Institute of Science and Technology (UNIST), Room 415, Advanced Material Research Building (103), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 44919, Republic of Korea.
| | - Byongkyu Lee
- Department of Energy Engineering, School of Energy and Chemical Engineering, Perovtronics Research Center, Low Dimensional Carbon Materials Center, Ulsan National Institute of Science and Technology (UNIST), Room 701-4, 2nd Engineering Building (104), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 44919, Republic of Korea.
| | - Seoyoung Kim
- Department of Energy Engineering, School of Energy and Chemical Engineering, Perovtronics Research Center, Low Dimensional Carbon Materials Center, Ulsan National Institute of Science and Technology (UNIST), Room 701-4, 2nd Engineering Building (104), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 44919, Republic of Korea.
| | - Changduk Yang
- Department of Energy Engineering, School of Energy and Chemical Engineering, Perovtronics Research Center, Low Dimensional Carbon Materials Center, Ulsan National Institute of Science and Technology (UNIST), Room 701-4, 2nd Engineering Building (104), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 44919, Republic of Korea.
| | - Oh-Hoon Kwon
- Department of Chemistry, College of Natural Sciences, Ulsan National Institute of Science and Technology (UNIST), Room 415, Advanced Material Research Building (103), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 44919, Republic of Korea. .,Center for Soft and Living Matter, Institute for Basic Science (IBS), Ulsan 44919, Republic of Korea
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9
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Gu C, Zhang H, Liu Y, Yu J, Pan J, Luo G, Shen Q, Tang J, Hu J. Time-Domain Observation of Spectral Diffusion in Defective ZnO. ACS OMEGA 2021; 6:15442-15447. [PMID: 34151122 PMCID: PMC8210433 DOI: 10.1021/acsomega.1c01890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Accepted: 05/18/2021] [Indexed: 06/13/2023]
Abstract
Defects can affect all aspects of materials by altering their electronic structures and mediating the carrier dynamics. However, in the past decades, most research efforts were restricted to nonstoichiometric defects, while the effects of high-density defects on the carrier dynamics of semiconductors remained elusive. In this work, using transient absorption spectroscopy, we have observed for the first time a hybrid carrier relaxation dynamics with the feature of a Poisson-like retard shoulder in a time-domain profile in highly defective ZnO crystals. This novel behavior has been attributed to the spectral diffusion within continuum defect states, which is further confirmed by a proposed diffusion (in energy space) controlled carrier dynamic model. Our results thus reveal an alternative energy decay channel in highly defective crystals and may provide a new route for defect engineering.
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Affiliation(s)
- Chun Gu
- Laboratory
for Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China
- State
Key Laboratory for Environment-Friendly Energy Materials, Southwest University of Science and Technology, Mianyang 621010, China
- State
Key Laboratory of Advanced Technology for Materials Synthesis and
Processing, Wuhan University of Technology, Wuhan 430070, China
| | - Hang Zhang
- Laboratory
for Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China
- State
Key Laboratory for Environment-Friendly Energy Materials, Southwest University of Science and Technology, Mianyang 621010, China
| | - Yonggang Liu
- State
Key Laboratory for Environment-Friendly Energy Materials, Southwest University of Science and Technology, Mianyang 621010, China
| | - Junhong Yu
- Laboratory
for Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China
| | - Junheng Pan
- Institute
of Technological Science, Wuhan University, Wuhan 430072, China
| | - Guoqiang Luo
- State
Key Laboratory of Advanced Technology for Materials Synthesis and
Processing, Wuhan University of Technology, Wuhan 430070, China
| | - Qiang Shen
- State
Key Laboratory of Advanced Technology for Materials Synthesis and
Processing, Wuhan University of Technology, Wuhan 430070, China
| | - Jau Tang
- Institute
of Technological Science, Wuhan University, Wuhan 430072, China
| | - Jianbo Hu
- Laboratory
for Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China
- State
Key Laboratory for Environment-Friendly Energy Materials, Southwest University of Science and Technology, Mianyang 621010, China
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10
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Shaikh J, Congrave DG, Forster A, Minotto A, Cacialli F, Hele TJH, Penfold TJ, Bronstein H, Clarke TM. Intrinsic photogeneration of long-lived charges in a donor-orthogonal acceptor conjugated polymer. Chem Sci 2021; 12:8165-8177. [PMID: 34194707 PMCID: PMC8208312 DOI: 10.1039/d1sc00919b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 05/08/2021] [Indexed: 11/21/2022] Open
Abstract
Efficient charge photogeneration in conjugated polymers typically requires the presence of a second component to act as electron acceptor. Here, we report a novel low band-gap conjugated polymer with a donor/orthogonal acceptor motif: poly-2,6-(4,4-dihexadecyl-4H-cyclopenta [2,1-b:3,4-b']dithiophene)-alt-2,6-spiro [cyclopenta[2,1-b:3,4-b']dithiophene-4,9'-fluorene]-2',7'-dicarbonitrile, referred to as PCPDT-sFCN. The role of the orthogonal acceptor is to spatially isolate the LUMO from the HOMO, allowing for negligible exchange energy between electrons in these orbitals and minimising the energy gap between singlet and triplet charge transfer states. We employ ultrafast and microsecond transient absorption spectroscopy to demonstrate that, even in the absence of a separate electron acceptor, PCPDT-sFCN shows efficient charge photogeneration in both pristine solution and film. This efficient charge generation is a result of an isoenergetic singlet/triplet charge transfer state equilibrium acting as a reservoir for charge carrier formation. Furthermore, clear evidence of enhanced triplet populations, which form in less than 1 ps, is observed. Using group theory, we show that this ultrafast triplet formation is due to highly efficient, quantum mechanically allowed intersystem crossing between the bright, initially photoexcited local singlet state and the triplet charge transfer state. Remarkably, the free charges that form via the charge transfer state are extraordinarily long-lived with millisecond lifetimes, possibly due to the stabilisation imparted by the spatial separation of PCPDT-sFCN's donor and orthogonal acceptor motifs. The efficient generation of long-lived charge carriers in a pristine polymer paves the way for single-material applications such as organic photovoltaics and photodetectors.
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Affiliation(s)
- Jordan Shaikh
- Department of Chemistry, University College London Christopher Ingold Building London WC1H 0AJ UK
| | - Daniel G Congrave
- Department of Chemistry, University of Cambridge Lensfield Road Cambridge CB2 1EW UK
| | - Alex Forster
- Department of Chemistry, University of Cambridge Lensfield Road Cambridge CB2 1EW UK
| | - Alessandro Minotto
- Department of Physics, University College London Gower Street London WC1E 6BT UK
| | - Franco Cacialli
- Department of Physics, University College London Gower Street London WC1E 6BT UK
| | - Timothy J H Hele
- Department of Chemistry, University College London Christopher Ingold Building London WC1H 0AJ UK
| | - Thomas J Penfold
- Chemistry - School of Natural and Environmental Sciences, Newcastle University Newcastle upon Tyne NE1 7RU UK
| | - Hugo Bronstein
- Department of Chemistry, University of Cambridge Lensfield Road Cambridge CB2 1EW UK
| | - Tracey M Clarke
- Department of Chemistry, University College London Christopher Ingold Building London WC1H 0AJ UK
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11
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Ghosh A, Ghosh S, Ghosh G, Patra A. Implications of relaxation dynamics of collapsed conjugated polymeric nanoparticles for light-harvesting applications. Phys Chem Chem Phys 2021; 23:14549-14563. [DOI: 10.1039/d1cp01618k] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The mechanism of the formation of nanoparticles (collapsed state) from the extended state of polymers and their ultrafast excited state relaxation dynamics are illustrated.
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Affiliation(s)
- Arnab Ghosh
- School of Materials Sciences
- Indian Association for the Cultivation of Science
- Kolkata 700032
- India
| | - Srijon Ghosh
- School of Materials Sciences
- Indian Association for the Cultivation of Science
- Kolkata 700032
- India
| | - Goutam Ghosh
- School of Materials Sciences
- Indian Association for the Cultivation of Science
- Kolkata 700032
- India
| | - Amitava Patra
- School of Materials Sciences
- Indian Association for the Cultivation of Science
- Kolkata 700032
- India
- Institute of Nano Science and Technology
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12
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Rahman M, Tian H, Edvinsson T. Revisiting the Limiting Factors for Overall Water-Splitting on Organic Photocatalysts. Angew Chem Int Ed Engl 2020; 59:16278-16293. [PMID: 32329950 PMCID: PMC7540687 DOI: 10.1002/anie.202002561] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Indexed: 12/02/2022]
Abstract
In pursuit of inexpensive and earth abundant photocatalysts for solar hydrogen production from water, conjugated polymers have shown potential to be a viable alternative to widely used inorganic counterparts. The photocatalytic performance of polymeric photocatalysts, however, is very poor in comparison to that of inorganic photocatalysts. Most of the organic photocatalysts are active in hydrogen production only when a sacrificial electron donor (SED) is added into the solution, and their high performances often rely on presence of noble metal co-catalyst (e.g. Pt). For pursuing a carbon neutral and cost-effective green hydrogen production, unassisted hydrogen production solely from water is one of the critical requirements to translate a mere bench-top research interest into the real world applications. Although this is a generic problem for both inorganic and organic types of photocatalysts, organic photocatalysts are mostly investigated in the half-reaction, and have so far shown limited success in hydrogen production from overall water-splitting. To make progress, this article exclusively discusses critical factors that are limiting the overall water-splitting in organic photocatalysts. Additionally, we also have extended the discussion to issues related to stability, accurate reporting of the hydrogen production as well as challenges to be resolved to reach 10 % STH (solar-to-hydrogen) conversion efficiency.
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Affiliation(s)
- Mohammad Rahman
- Department of Materials Sciences and EngineeringDivision of Solid State PhysicsAngstrom LaboratoryUppsala UniversitySweden
| | - Haining Tian
- Department of ChemistryDivision of Physical chemistryAngstrom LaboratoryUppsala UniversitySweden
| | - Tomas Edvinsson
- Department of Materials Sciences and EngineeringDivision of Solid State PhysicsAngstrom LaboratoryUppsala UniversitySweden
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13
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Rahman M, Tian H, Edvinsson T. Revisiting the Limiting Factors for Overall Water‐Splitting on Organic Photocatalysts. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202002561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Mohammad Rahman
- Department of Materials Sciences and EngineeringDivision of Solid State PhysicsAngstrom LaboratoryUppsala University Sweden
| | - Haining Tian
- Department of ChemistryDivision of Physical chemistryAngstrom LaboratoryUppsala University Sweden
| | - Tomas Edvinsson
- Department of Materials Sciences and EngineeringDivision of Solid State PhysicsAngstrom LaboratoryUppsala University Sweden
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14
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Ghosh A, Ghosh S, Ghosh G, Jana B, Patra A. Global and target analysis of relaxation processes of the collapsed state of P3HT polymer nanoparticles. Phys Chem Chem Phys 2020; 22:2229-2237. [DOI: 10.1039/c9cp06600d] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Organic–inorganic hetero-structures composed of P3HT PNPs and Au NPs have been designed for efficient light harvesting systems. Here electron transfer occurs from vibrationally hot S1 state and delocalized collective state (CLS) of PNPs to Au NPs.
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Affiliation(s)
- Arnab Ghosh
- School of Materials Sciences
- Indian Association for the Cultivation of Science
- Kolkata 700032
- India
| | - Srijon Ghosh
- School of Materials Sciences
- Indian Association for the Cultivation of Science
- Kolkata 700032
- India
| | - Goutam Ghosh
- School of Materials Sciences
- Indian Association for the Cultivation of Science
- Kolkata 700032
- India
| | - Bikash Jana
- School of Materials Sciences
- Indian Association for the Cultivation of Science
- Kolkata 700032
- India
| | - Amitava Patra
- School of Materials Sciences
- Indian Association for the Cultivation of Science
- Kolkata 700032
- India
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15
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Qian J, Zhang Y, Liu X, Xia J. Carbazole and fluorene polyaniline derivatives: Synthesis, properties and application as multiple stimuli-responsive fluorescent chemosensor. Talanta 2019; 204:592-601. [PMID: 31357339 DOI: 10.1016/j.talanta.2019.06.038] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 06/04/2019] [Accepted: 06/09/2019] [Indexed: 11/26/2022]
Abstract
Development of conjugated polymers with fluorescence sensing characteristics has received close attention from researchers in fields of environmental protection, biosensing and toxins detection on food. In this paper, novel polyaniline derivatives of poly(9-methyl-9H-carbazol-3-amine) and poly(9,9-dihexyl-9H-fluoren-2-amine) are prepared by facile chemical polymerization. Then they are characterized with NMR (Nuclear Magnetic Resonance), GPC (Gel Permeation Chromatography), XRD (X-Ray Diffraction), FT-IR (Fourier Transform Infrared spectroscopy), FL (Fluorescence spectrometry) and UV-vis (Ultraviolet-visible spectroscopy) characterizations and further applied to the fluorescence detection of different acids and amines. Moreover, the obtained poly(9-methyl-9H-carbazol-3-amine) displays excellent fluorescence properties in the detection for both acids and amines. Besides, this poly(9-methyl-9H-carbazol-3-amine) can not only be used for fluorescence detection in solution, but also can be prepared into solid state and applied in the gas phase fluorescence detection. This work has greatly expanded the scope of application to these polyaniline derivatives materials, opening a new path for the researches on multi-functional chemosensor.
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Affiliation(s)
- Junning Qian
- Hubei Key Lab on Organic and Polymeric Optoelectronic Materials, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, China
| | - Yedong Zhang
- Hubei Key Lab on Organic and Polymeric Optoelectronic Materials, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, China
| | - Xinghai Liu
- School of Printing & Packaging, Wuhan University, Wuhan, 430072, China.
| | - Jiangbin Xia
- Hubei Key Lab on Organic and Polymeric Optoelectronic Materials, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, China; Engineering Research Center of Organosilicon Compounds & Materials, Ministry of Education, College of Chemistry and Molecular Science, Wuhan University, Wuhan, 430072, China.
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16
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Huang X, Ji D, Fuchs H, Hu W, Li T. Recent Progress in Organic Phototransistors: Semiconductor Materials, Device Structures and Optoelectronic Applications. CHEMPHOTOCHEM 2019. [DOI: 10.1002/cptc.201900198] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Xianhui Huang
- School of Chemistry and Chemical Engineering andKey Laboratory of Thin Film and Microfabrication (Ministry of Education)Shanghai Jiao Tong University Shanghai 200240 China
| | - Deyang Ji
- Institute of Molecular Aggregation ScienceTianjin University Tianjin 300072 China
- Physikalisches InstitutWestfälische Wilhelms-Universität Wilhelm-Klemm-Straße 10 48149 Münster Germany
| | - Harald Fuchs
- Physikalisches InstitutWestfälische Wilhelms-Universität Wilhelm-Klemm-Straße 10 48149 Münster Germany
| | - Wenping Hu
- Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072 China
| | - Tao Li
- School of Chemistry and Chemical Engineering andKey Laboratory of Thin Film and Microfabrication (Ministry of Education)Shanghai Jiao Tong University Shanghai 200240 China
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17
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Ghosh A, Ghosh S, Jana B, Patra A. Ultrafast Relaxation Processes of Conjugated Polymer Nanoparticles in the Presence of Au Nanoparticles. Chem Asian J 2019; 14:4681-4687. [DOI: 10.1002/asia.201900905] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 08/02/2019] [Indexed: 11/05/2022]
Affiliation(s)
- Arnab Ghosh
- School of Materials SciencesIndian Association for the Cultivation of Science Jadavpur Kolkata 700032 India
| | - Srijon Ghosh
- School of Materials SciencesIndian Association for the Cultivation of Science Jadavpur Kolkata 700032 India
| | - Bikash Jana
- School of Materials SciencesIndian Association for the Cultivation of Science Jadavpur Kolkata 700032 India
| | - Amitava Patra
- School of Materials SciencesIndian Association for the Cultivation of Science Jadavpur Kolkata 700032 India
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18
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Camacho R, Täuber D, Scheblykin IG. Fluorescence Anisotropy Reloaded-Emerging Polarization Microscopy Methods for Assessing Chromophores' Organization and Excitation Energy Transfer in Single Molecules, Particles, Films, and Beyond. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1805671. [PMID: 30721532 DOI: 10.1002/adma.201805671] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 11/12/2018] [Indexed: 06/09/2023]
Abstract
Fluorescence polarization is widely used to assess the orientation/rotation of molecules, and the excitation energy transfer between closely located chromophores. Emerging since the 1990s, single molecule fluorescence spectroscopy and imaging stimulate the application of light polarization for studying molecular organization and energy transfer beyond ensemble averaging. Here, traditional fluorescence polarization and linear dichroism methods used for bulk samples are compared with techniques specially developed for, or inspired by, single molecule fluorescence spectroscopy. Techniques for assessing energy transfer in anisotropic samples, where the traditional fluorescence anisotropy framework is not readily applicable, are discussed in depth. It is shown that the concept of a polarization portrait and the single funnel approximation can lay the foundation for alternative energy transfer metrics. Examples ranging from fundamental studies of photoactive materials (conjugated polymers, light-harvesting aggregates, and perovskite semiconductors) to Förster resonant energy transfer (FRET)-based biomedical imaging are presented. Furthermore, novel uses of light polarization for super-resolution optical imaging are mentioned as well as strategies for avoiding artifacts in polarization microscopy.
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Affiliation(s)
- Rafael Camacho
- Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001, Leuven, Belgium
| | - Daniela Täuber
- Chemical Physics and NanoLund, Lund University, P.O. Box 124, SE-22100, Lund, Sweden
- Biopolarisation, Leibniz Institute of Photonic Technology, Albert-Einstein-Str. 9, D-07745, Jena, Germany
- Institute of Solid State Physics, FSU Jena, Helmholtzweg 3, D-07743, Jena, Germany
| | - Ivan G Scheblykin
- Chemical Physics and NanoLund, Lund University, P.O. Box 124, SE-22100, Lund, Sweden
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19
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Denk O, Zheng K, Zigmantas D, Žídek K. Compressive imaging of transient absorption dynamics on the femtosecond timescale. OPTICS EXPRESS 2019; 27:10234-10246. [PMID: 31045167 DOI: 10.1364/oe.27.010234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 03/02/2019] [Indexed: 06/09/2023]
Abstract
Femtosecond spectroscopy is an important tool used for tracking rapid photoinduced processes in a variety of materials. To spatially map the processes in a sample would substantially expand the method's capabilities. This is, however, difficult to achieve, due to the necessity of using low-noise detection and maintaining feasible data acquisition time. Here, we demonstrate realization of an imaging pump-probe setup, featuring sub-100 fs temporal resolution, by using a straightforward modification of a standard pump-probe technique, which uses a randomly structured probe beam. The structured beam, made by a diffuser, enabled us to computationally reconstruct the maps of transient absorption dynamics based on the concept of compressed sensing. We demonstrate the setup's functionality in two proof-of-principle experiments, where we achieve spatial resolution of 20 μm. The presented concept provides a feasible route to imaging, by using the pump-probe technique and ultrafast spectroscopy in general.
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20
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Archer SA, Raza A, Dröge F, Robertson C, Auty AJ, Chekulaev D, Weinstein JA, Keane T, Meijer AJHM, Haycock JW, MacNeil S, Thomas JA. A dinuclear ruthenium(ii) phototherapeutic that targets duplex and quadruplex DNA. Chem Sci 2019; 10:3502-3513. [PMID: 30996941 PMCID: PMC6430095 DOI: 10.1039/c8sc05084h] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 02/14/2019] [Indexed: 02/06/2023] Open
Abstract
With the aim of developing a sensitizer for photodynamic therapy, a previously reported luminescent dinuclear complex that functions as a DNA probe in live cells was modified to produce a new iso-structural derivative containing RuII(TAP)2 fragments (TAP = 1,4,5,8-tetraazaphenanthrene). The structure of the new complex has been confirmed by a variety of techniques including single crystal X-ray analysis. Unlike its parent, the new complex displays Ru → L-based 3MLCT emission in both MeCN and water. Results from electrochemical studies and emission quenching experiments involving guanosine monophosphate are consistent with an excited state located on a TAP moiety. This hypothesis is further supported by detailed DFT calculations, which take into account solvent effects on excited state dynamics. Cell-free steady-state and time-resolved optical studies on the interaction of the new complex with duplex and quadruplex DNA show that the complex binds with high affinity to both structures and indicate that its photoexcited state is also quenched by DNA, a process that is accompanied by the generation of the guanine radical cation sites as photo-oxidization products. Like the parent complex, this new compound is taken up by live cells where it primarily localizes within the nucleus and displays low cytotoxicity in the absence of light. However, in complete contrast to [{RuII(phen)2}2(tpphz)]4+, the new complex is therapeutically activated by light to become highly phototoxic toward malignant human melanoma cell lines showing that it is a promising lead for the treatment of this recalcitrant cancer.
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Affiliation(s)
- Stuart A Archer
- Department of Chemistry , University of Sheffield , Brook Hill , Sheffield , S3 7HF , UK . ; Tel: +44 (0)114 222 9325
| | - Ahtasham Raza
- Materials Science & Engineering , University of Sheffield , Mappin St , Sheffield S1 3JD , UK . ;
| | - Fabian Dröge
- Department of Chemistry , University of Sheffield , Brook Hill , Sheffield , S3 7HF , UK . ; Tel: +44 (0)114 222 9325
| | - Craig Robertson
- Department of Chemistry , University of Sheffield , Brook Hill , Sheffield , S3 7HF , UK . ; Tel: +44 (0)114 222 9325
| | - Alexander J Auty
- Department of Chemistry , University of Sheffield , Brook Hill , Sheffield , S3 7HF , UK . ; Tel: +44 (0)114 222 9325
| | - Dimitri Chekulaev
- Department of Chemistry , University of Sheffield , Brook Hill , Sheffield , S3 7HF , UK . ; Tel: +44 (0)114 222 9325
| | - Julia A Weinstein
- Department of Chemistry , University of Sheffield , Brook Hill , Sheffield , S3 7HF , UK . ; Tel: +44 (0)114 222 9325
| | - Theo Keane
- Department of Chemistry , University of Sheffield , Brook Hill , Sheffield , S3 7HF , UK . ; Tel: +44 (0)114 222 9325
| | - Anthony J H M Meijer
- Department of Chemistry , University of Sheffield , Brook Hill , Sheffield , S3 7HF , UK . ; Tel: +44 (0)114 222 9325
| | - John W Haycock
- Materials Science & Engineering , University of Sheffield , Mappin St , Sheffield S1 3JD , UK . ;
| | - Sheila MacNeil
- Materials Science & Engineering , University of Sheffield , Mappin St , Sheffield S1 3JD , UK . ;
| | - James A Thomas
- Department of Chemistry , University of Sheffield , Brook Hill , Sheffield , S3 7HF , UK . ; Tel: +44 (0)114 222 9325
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21
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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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22
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Affiliation(s)
- Ayesha Kausar
- School of Natural Sciences, National University of Sciences and Technology (NUST), Islamabad, Pakistan
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23
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Meyer DL, Matsidik R, Fazzi D, Sommer M, Biskup T. Probing Exciton Delocalization in Organic Semiconductors: Insight from Time-Resolved Electron Paramagnetic Resonance and Magnetophotoselection Experiments. J Phys Chem Lett 2018; 9:7026-7031. [PMID: 30485108 DOI: 10.1021/acs.jpclett.8b03196] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Delocalization of excited states of organic semiconductors is directly related to their efficiency in devices. Time-resolved electron paramagnetic resonance spectroscopy provides unique capabilities in this respect because of its high spectral resolution and capability to probe the geometry and extent of excitons. Using magnetophotoselection experiments, the mode of exciton delocalization, along the backbone or parallel to the π-π stacking direction of the conjugated polymers, can be revealed. We demonstrate the robustness of this approach by applying it to building blocks of a prototypical conjugated polymer showing a symmetry of their excited states being far from ideal for this experiment. This renders magnetophotoselection superior to other approaches because it is applicable to a wealth of other organic semiconductors. The insight gained into exciton delocalization is crucial to the structure-function relationship of organic semiconductors and directly relevant for developing highly efficient materials.
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Affiliation(s)
- Deborah L Meyer
- Institut für Physikalische Chemie , Albert-Ludwigs-Universität Freiburg , 79104 Freiburg , Germany
| | - Rukiya Matsidik
- Institut für Makromolekulare Chemie , Albert-Ludwigs-Universität Freiburg , 79104 Freiburg , Germany
| | - Daniele Fazzi
- Institut für Physikalische Chemie , Universität zu Köln , 50939 Köln , Germany
| | - Michael Sommer
- Institut für Makromolekulare Chemie , Albert-Ludwigs-Universität Freiburg , 79104 Freiburg , Germany
- Institut für Chemie, Polymerchemie , Technische Universität Chemnitz , 09111 Chemnitz , Germany
| | - Till Biskup
- Institut für Physikalische Chemie , Albert-Ludwigs-Universität Freiburg , 79104 Freiburg , Germany
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24
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Zhang X, Dong H, Hu W. Organic Semiconductor Single Crystals for Electronics and Photonics. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1801048. [PMID: 30039629 DOI: 10.1002/adma.201801048] [Citation(s) in RCA: 162] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 04/22/2018] [Indexed: 05/26/2023]
Abstract
Organic semiconducting single crystals (OSSCs) are ideal candidates for the construction of high-performance optoelectronic devices/circuits and a great platform for fundamental research due to their long-range order, absence of grain boundaries, and extremely low defect density. Impressive improvements have recently been made in organic optoelectronics: the charge-carrier mobility is now over 10 cm2 V-1 s-1 and the fluorescence efficiency reaches 90% for many OSSCs. Moreover, high mobility and strong emission can be integrated into a single OSSC, for example, showing a mobility of up to 34 cm2 V-1 s-1 and a photoluminescence yield of 41.2%. These achievements are attributed to the rational design and synthesis of organic semiconductors as well as improvements in preparation technology for crystals, which accelerate the application of OSSCs in devices and circuits, such as organic field-effect transistors, organic photodetectors, organic photovoltaics, organic light-emitting diodes, organic light-emitting transistors, and even electrically pumped organic lasers. In this context, an overview of these fantastic advancements in terms of the fundamental insights into developing high-performance organic semiconductors, efficient strategies for yielding desirable high-quality OSSCs, and their applications in optoelectronic devices and circuits is presented. Finally, an overview of the development of OSSCs along with current challenges and future research directions is provided.
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Affiliation(s)
- Xiaotao Zhang
- Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Sciences, Tianjin University, No. 92#, Weijin Road, Tianjin, 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300072, China
| | - Huanli Dong
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
| | - Wenping Hu
- Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Sciences, Tianjin University, No. 92#, Weijin Road, Tianjin, 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300072, China
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
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25
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Wang Y, Ke Y, Zhao Y. The hierarchical and perturbative forms of stochastic Schrödinger equations and their applications to carrier dynamics in organic materials. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2018. [DOI: 10.1002/wcms.1375] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Yu‐Chen Wang
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, Fujian Provincial Key Lab of Theoretical and Computational Chemistry, and College of Chemistry and Chemical Engineering, Xiamen University Xiamen China
| | - Yaling Ke
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, Fujian Provincial Key Lab of Theoretical and Computational Chemistry, and College of Chemistry and Chemical Engineering, Xiamen University Xiamen China
| | - Yi Zhao
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, Fujian Provincial Key Lab of Theoretical and Computational Chemistry, and College of Chemistry and Chemical Engineering, Xiamen University Xiamen China
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26
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Klein JR, Scholz M, Oum K, Lenzer T. Intramolecular and interfacial dynamics of triarylamine-based hole transport materials. Photochem Photobiol Sci 2018; 17:722-733. [DOI: 10.1039/c8pp00030a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Hole injection across interfaces is fast but critically depends on good contact between the hole transfer and light-harvesting materials.
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Affiliation(s)
| | - Mirko Scholz
- Universität Siegen
- Physikalische Chemie
- 57076 Siegen
- Germany
| | - Kawon Oum
- Universität Siegen
- Physikalische Chemie
- 57076 Siegen
- Germany
| | - Thomas Lenzer
- Universität Siegen
- Physikalische Chemie
- 57076 Siegen
- Germany
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27
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Shimazaki T, Tashiro M, Nakajima T. Theoretical study on mesoscopic-size impurity effects in the charge separation process of organic photocells. Phys Chem Chem Phys 2018; 20:14846-14854. [DOI: 10.1039/c7cp08125a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A bulk-heterojunction structure is often employed to develop high-performance organic photocells, in which the donor and acceptor regions are complexly intertwined.
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Affiliation(s)
- Tomomi Shimazaki
- Kobe University
- Graduate School of System Informatics
- Kobe 657-8501
- Japan
- RIKEN
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28
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Penwell SB, Ginsberg LDS, Noriega R, Ginsberg NS. Resolving ultrafast exciton migration in organic solids at the nanoscale. NATURE MATERIALS 2017; 16:1136-1141. [PMID: 28920937 DOI: 10.1038/nmat4975] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Accepted: 07/25/2017] [Indexed: 05/16/2023]
Abstract
Effectiveness of molecular-based light harvesting relies on transport of excitons to charge-transfer sites. Measuring exciton migration, however, has been challenging because of the mismatch between nanoscale migration lengths and the diffraction limit. Instead of using bulk substrate quenching methods, here we define quenching boundaries all-optically with sub-diffraction resolution, thus characterizing spatiotemporal exciton migration on its native nanometre and picosecond scales. By transforming stimulated emission depletion microscopy into a time-resolved ultrafast approach, we measure a 16-nm migration length in poly(2,5-di(hexyloxy)cyanoterephthalylidene) conjugated polymer films. Combined with Monte Carlo exciton hopping simulations, we show that migration in these films is essentially diffusive because intrinsic chromophore energetic disorder is comparable to chromophore inhomogeneous broadening. Our approach will enable previously unattainable correlation of local material structure to exciton migration character, applicable not only to photovoltaic or display-destined organic semiconductors but also to explaining the quintessential exciton migration exhibited in photosynthesis.
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Affiliation(s)
- Samuel B Penwell
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Lucas D S Ginsberg
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Rodrigo Noriega
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Naomi S Ginsberg
- Department of Chemistry, University of California, Berkeley, California 94720, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
- Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
- Kavli Energy NanoScience Institute, Berkeley, California 94720, USA
- Department of Physics, University of California, Berkeley, California 94720, USA
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29
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Lee YH, Jang M, Lee MY, Kweon OY, Oh JH. Flexible Field-Effect Transistor-Type Sensors Based on Conjugated Molecules. Chem 2017. [DOI: 10.1016/j.chempr.2017.10.005] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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30
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Grupp A, Ehrenreich P, Kalb J, Budweg A, Schmidt-Mende L, Brida D. Incoherent Pathways of Charge Separation in Organic and Hybrid Solar Cells. J Phys Chem Lett 2017; 8:4858-4864. [PMID: 28925705 DOI: 10.1021/acs.jpclett.7b01873] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In this work, we investigate the exciton dissociation dynamics occurring at the donor:acceptor interface in organic and hybrid blends employed in the realization of photovoltaic cells. Fundamental differences in the charge separation process are studied with the organic semiconductor polymer poly(3-hexylthiophene) (P3HT) and either [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) or titanium dioxide (TiO2) acting as the acceptor. By using ultrafast broad-band transient absorption spectroscopy with few-fs temporal resolution, we observe that in both cases the incoherent formation of free charges dominates the charge generation process. From the optical response of the polymer and by tracking the excited-state absorption, we extract pivotal similarities in the incoherent energy pathways that follow the impulsive excitation. On time scales shorter than 200 fs, we observe that the two acceptors display similar dynamics in the exciton delocalization. Significant differences arise only on longer time scales with only an impact on the overall photocarrier generation efficiency.
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Affiliation(s)
- Alexander Grupp
- Department of Physics and Center for Applied Photonics, University of Konstanz , D-78457 Konstanz, Germany
| | - Philipp Ehrenreich
- Department of Physics and Center for Applied Photonics, University of Konstanz , D-78457 Konstanz, Germany
| | - Julian Kalb
- Department of Physics and Center for Applied Photonics, University of Konstanz , D-78457 Konstanz, Germany
| | - Arne Budweg
- Department of Physics and Center for Applied Photonics, University of Konstanz , D-78457 Konstanz, Germany
| | - Lukas Schmidt-Mende
- Department of Physics and Center for Applied Photonics, University of Konstanz , D-78457 Konstanz, Germany
| | - Daniele Brida
- Department of Physics and Center for Applied Photonics, University of Konstanz , D-78457 Konstanz, Germany
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31
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Dimitriev OP. Effect of Confinement on Photophysical Properties of P3HT Chains in PMMA Matrix. NANOSCALE RESEARCH LETTERS 2017; 12:510. [PMID: 28853046 PMCID: PMC5574825 DOI: 10.1186/s11671-017-2270-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Accepted: 08/09/2017] [Indexed: 06/07/2023]
Abstract
The influence of arrangement of poly(3-hexylthiophene) (P3HT) chains embedded into poly(methyl methacrylate) (PMMA) matrix on photophysical properties, such as electronic absorption spectrum, band gap, and photoluminescence quantum yield, of the formed P3HT aggregates have been studied. It has been found that variation of P3HT fraction in PMMA matrix from 25 to 2 wt% is accompanied with the increasing quantum yield of photoluminescence, red shift of the band gap, and structural change of P3HT crystallites. The above changes are accompanied with disruption of the continuous network of P3HT fraction into smaller P3HT particles with size ranged from several microns to several tens of nanometers. The results are interpreted in terms of the changing intermolecular packing and reduced intramolecular torsional disorder. It is discussed that the most contribution to the above changes comes from P3HT molecules at the interface of P3HT cluster and PMMA environment.
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Affiliation(s)
- Oleg P Dimitriev
- V. Lashkaryov Institute of Semiconductor Physics, Natl. Acad. of Sci. of Ukraine, Prospect Nauki, 41, Kiev, 03028, Ukraine.
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Ponseca CS, Chábera P, Uhlig J, Persson P, Sundström V. Ultrafast Electron Dynamics in Solar Energy Conversion. Chem Rev 2017; 117:10940-11024. [DOI: 10.1021/acs.chemrev.6b00807] [Citation(s) in RCA: 211] [Impact Index Per Article: 30.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Carlito S. Ponseca
- Division
of Chemical Physics, Chemical Center, and ‡Theoretical Chemistry Division,
Chemical Center, Lund University, Box 124, Lund SE-221 00, Sweden
| | - Pavel Chábera
- Division
of Chemical Physics, Chemical Center, and ‡Theoretical Chemistry Division,
Chemical Center, Lund University, Box 124, Lund SE-221 00, Sweden
| | - Jens Uhlig
- Division
of Chemical Physics, Chemical Center, and ‡Theoretical Chemistry Division,
Chemical Center, Lund University, Box 124, Lund SE-221 00, Sweden
| | - Petter Persson
- Division
of Chemical Physics, Chemical Center, and ‡Theoretical Chemistry Division,
Chemical Center, Lund University, Box 124, Lund SE-221 00, Sweden
| | - Villy Sundström
- Division
of Chemical Physics, Chemical Center, and ‡Theoretical Chemistry Division,
Chemical Center, Lund University, Box 124, Lund SE-221 00, Sweden
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33
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Peteanu LA, Chowdhury S, Wildeman J, Sfeir MY. Exciton–Exciton Annihilation as a Probe of Interchain Interactions in PPV–Oligomer Aggregates. J Phys Chem B 2017; 121:1707-1714. [DOI: 10.1021/acs.jpcb.6b11250] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Linda A. Peteanu
- Department
of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Sanchari Chowdhury
- Department
of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Jurjen Wildeman
- Zernike Institute of Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Matthew Y. Sfeir
- Center
for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, United States
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34
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Shimazaki T, Nakajima T. A theoretical study on hot charge-transfer states and dimensional effects of organic photocells based on an ideal diode model. Phys Chem Chem Phys 2017; 19:12517-12526. [DOI: 10.1039/c7cp01455d] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This paper discusses an ideal diode model with hot charge-transfer (CT) states to analyze the power conversion efficiency of an organic photocell.
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Affiliation(s)
- Tomomi Shimazaki
- RIKEN
- Advanced Institute for Computational Science 7-1-26 Minatojima-minami-machi
- Chuo-ku
- Kobe
- Japan
| | - Takahito Nakajima
- RIKEN
- Advanced Institute for Computational Science 7-1-26 Minatojima-minami-machi
- Chuo-ku
- Kobe
- Japan
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35
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Li Y, Ullrich CA. The particle-hole map: Formal derivation and numerical implementation. J Chem Phys 2016; 145:164107. [DOI: 10.1063/1.4966036] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Yonghui Li
- Department of Physics, Tianjin University, 92 Weijin Road, Tianjin 300072,China
- Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211, USA
| | - Carsten A. Ullrich
- Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211, USA
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36
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Shimazaki T, Nakajima T. Theoretical study on the cooperative exciton dissociation process based on dimensional and hot charge-transfer state effects in an organic photocell. J Chem Phys 2016; 144:234906. [DOI: 10.1063/1.4953905] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
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37
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Menezes DB, de Fátima Curcino da Silva S, Akcelrud L, Zambon Atvars TD, Balogh DT, Mascarenhas YP, Marletta A, Tozoni JR. Effects of the host molecular dynamics on the photoemission temperature dependence of host/guest photoluminescent blends. POLYMER 2016. [DOI: 10.1016/j.polymer.2016.03.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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38
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Song P, Li Y, Ma F, Pullerits T, Sun M. Photoinduced Electron Transfer in Organic Solar Cells. CHEM REC 2016; 16:734-53. [PMID: 26853631 DOI: 10.1002/tcr.201500244] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Indexed: 11/07/2022]
Abstract
Electron transfer (ET) is the key process in light-driven charge separation reactions in organic solar cells. The current review summarizes the progress in theoretical modelling of ET in these materials. First we give an account of ET, with a description originating from Marcus theory. We systematically go through all the relevant parameters and show how they depend on different material properties, and discuss the consequences such dependencies have for the performance of the devices. Finally, we present a set of visualization methods which have proven to be very useful in analyzing the elementary processes in absorption and charge separation events. Such visualization tools help us to understand the properties of the photochemical and photobiological systems in solar cells.
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Affiliation(s)
- Peng Song
- Department of Physics, Liaoning University, Shenyang, 110036, P. R. China.,Beijing National Laboratory for Condensed Matter Physics, Institute of Physics Chinese Academy of Science, Beijing, 100190, P. R. China.,State Key laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics Chinese Academy of Science, Dalian, 116023, P. R. China
| | - Yuanzuo Li
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics Chinese Academy of Science, Beijing, 100190, P. R. China.,College of Science, Northeast Forestry University, Harbin, 150040, P. R. China
| | - Fengcai Ma
- Department of Physics, Liaoning University, Shenyang, 110036, P. R. China
| | - Tõnu Pullerits
- Department of Chemical Physics, Lund University, Box 124, Lund, 22100, Sweden.,State Key laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics Chinese Academy of Science, Dalian, 116023, P. R. China
| | - Mengtao Sun
- Department of Physics, Liaoning University, Shenyang, 110036, P. R. China.,Beijing National Laboratory for Condensed Matter Physics, Institute of Physics Chinese Academy of Science, Beijing, 100190, P. R. China
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39
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Bakulin AA, Silva C, Vella E. Ultrafast Spectroscopy with Photocurrent Detection: Watching Excitonic Optoelectronic Systems at Work. J Phys Chem Lett 2016; 7:250-8. [PMID: 26711855 PMCID: PMC4819534 DOI: 10.1021/acs.jpclett.5b01955] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 12/29/2015] [Indexed: 05/22/2023]
Abstract
While ultrafast spectroscopy with photocurrent detection was almost unknown before 2012, in the last 3 years, a number of research groups from different fields have independently developed ultrafast electric probe approaches and reported promising pilot studies. Here, we discuss these recent advances and provide our perspective on how photocurrent detection successfully overcomes many limitations of all-optical methods, which makes it a technique of choice when device photophysics is concerned. We also highlight compelling existing problems and research questions and suggest ways for further development, outlining the potential breakthroughs to be expected in the near future using photocurrent ultrafast optical probes.
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Affiliation(s)
- Artem A. Bakulin
- Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Carlos Silva
- Département de physique & Regroupement
québécois sur les matériaux de pointe, Université de Montréal, C.P. 6128, Succursale centre-ville, Montréal, Québec H3C 3J7, Canada
| | - Eleonora Vella
- Département de physique & Regroupement
québécois sur les matériaux de pointe, Université de Montréal, C.P. 6128, Succursale centre-ville, Montréal, Québec H3C 3J7, Canada
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40
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Mewes SA, Mewes JM, Dreuw A, Plasser F. Excitons in poly(para phenylene vinylene): a quantum-chemical perspective based on high-level ab initio calculations. Phys Chem Chem Phys 2016; 18:2548-63. [DOI: 10.1039/c5cp07077e] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Exciton analyses of high-level quantum-chemical computations for poly(paraphenylene vinylene) reveal the nature of the excitonic bands in PPV oligomers.
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Affiliation(s)
- Stefanie A. Mewes
- Interdisciplinary Center for Scientific Computing
- Ruprecht-Karls University
- D-69120 Heidelberg
- Germany
| | - Jan-Michael Mewes
- Interdisciplinary Center for Scientific Computing
- Ruprecht-Karls University
- D-69120 Heidelberg
- Germany
| | - Andreas Dreuw
- Interdisciplinary Center for Scientific Computing
- Ruprecht-Karls University
- D-69120 Heidelberg
- Germany
| | - Felix Plasser
- Interdisciplinary Center for Scientific Computing
- Ruprecht-Karls University
- D-69120 Heidelberg
- Germany
- Institute for Theoretical Chemistry
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41
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Lukin L. Initial spatial distribution of geminate charge carriers photogenerated in doped conjugated polymers. Chem Phys 2015. [DOI: 10.1016/j.chemphys.2015.09.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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42
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Cho SY, Jeon HJ, Yoo HW, Cho KM, Jung WB, Kim JS, Jung HT. Highly Enhanced Fluorescence Signals of Quantum Dot-Polymer Composite Arrays Formed by Hybridization of Ultrathin Plasmonic Au Nanowalls. NANO LETTERS 2015; 15:7273-7280. [PMID: 26455592 DOI: 10.1021/acs.nanolett.5b02355] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Enhancement of the fluorescence intensity of quantum dot (QD)-polymer nanocomposite arrays is an important issue in QD studies because of the significant reduction of fluorescence signals of such arrays due to nonradiative processes in densely packed polymer chains in solid films. In this study, we enhance the fluorescence intensity of such arrays without significantly reducing their optical transparency. Enhanced fluorescence is achieved by hybridizing ultrathin plasmonic Au nanowalls onto the sidewalls of the arrays via single-step patterning and hybridization. The plasmonic Au nanowall induces metal-enhanced fluorescence, resulting in a maximum 7-fold enhancement of the fluorescence signals. We also prepare QD nanostructures of various shapes and sizes by controlling the dry etching time. In the near future, this facile approach can be used for fluorescence enhancement of colloidal QDs with plasmonic hybrid structures. Such structures can be used as optical substrates for imaging applications and for fabrication of QD-LED devices.
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Affiliation(s)
- Soo-Yeon Cho
- Department of Chemical and Biomolecular Engineering (BK-21 Plus), Korea Advanced Institute of Science and Technology (KAIST) , 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea
| | - Hwan-Jin Jeon
- Department of Nano-Structured Materials Research, Korea National Nanofab Center , Daejeon, Republic of Korea
| | - Hae-Wook Yoo
- Defence Advanced R&D Center, Agency for Defense Development , Daejeon 305-600, Korea
| | - Kyeong Min Cho
- Department of Chemical and Biomolecular Engineering (BK-21 Plus), Korea Advanced Institute of Science and Technology (KAIST) , 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea
| | - Woo-Bin Jung
- Department of Chemical and Biomolecular Engineering (BK-21 Plus), Korea Advanced Institute of Science and Technology (KAIST) , 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea
| | - Jong-Seon Kim
- Department of Chemical and Biomolecular Engineering (BK-21 Plus), Korea Advanced Institute of Science and Technology (KAIST) , 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea
| | - Hee-Tae Jung
- Department of Chemical and Biomolecular Engineering (BK-21 Plus), Korea Advanced Institute of Science and Technology (KAIST) , 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea
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43
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Direct monitoring of bias-dependent variations in the exciton formation ratio of working organic light emitting diodes. Sci Rep 2015; 5:15533. [PMID: 26487499 PMCID: PMC4614446 DOI: 10.1038/srep15533] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 09/28/2015] [Indexed: 11/20/2022] Open
Abstract
In typical operation of organic light emitting diodes (OLEDs), excitons are assumed to generate with a ratio of 1:3 for singlet and triplet excitons, respectively, based on a simple spin statistics model. This assumption has been used in designing efficient OLEDs. Despite the larger generation ratio of triplet excitons, physical properties of fluorescent OLEDs are usually evaluated only through the electroluminescence (EL) intensity from singlets and the behaviors of triplets during the LED operation are virtually black-boxed, because the triplets are mostly non-emissive. Here, we employ transient spectroscopy combined with LED-operation for directly monitoring the non-emissive triplets of working OLEDs. The spectroscopic techniques are performed simultaneously with EL- and current measurements under various operation biases. The simultaneous measurements reveal that the relative formation ratio of singlet-to-triplet excitons dramatically changes with the magnitude of bias. The measurements also show that the generation efficiency of singlets scales with the bias, whereas that of triplets is nearly bias-independent. These features of the formation ratio and efficiency are compatibly explained by considering the yield of intersystem crossing and the energy separation of excitons from electron-hole pairs. The obtained findings via the spectroscopic measurements enable prediction of the formation pathways in OLEDs.
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44
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Romero-Servin S, Villa MDA, Carriles R, Ramos-Ortíz G, Maldonado JL, Rodríguez M, Güizado-Rodríguez M. Photophysical Study of Polymer-Based Solar Cells with an Organo-Boron Molecule in the Active Layer. MATERIALS 2015; 8:4258-4272. [PMID: 28793438 PMCID: PMC5455641 DOI: 10.3390/ma8074258] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 06/09/2015] [Accepted: 07/06/2015] [Indexed: 11/16/2022]
Abstract
Our group previously reported the synthesis of four polythiophene derivatives (P1-P4) used for solar cells. The cells were prepared under room conditions by spin coating, leading to low efficiencies. However, after the addition of 6-nitro-3-(E)-3-(4-dimethylaminophenyl)allylidene)-2,3-dihydrobenzo[d]-[1,3,2] oxazaborole (M1) to their active layers, the efficiencies of the cells showed approximately a two-fold improvement. In this paper, we study this enhancement mechanism by performing ultrafast transient absorption (TA) experiments on the active layer of the different cells. Our samples consisted of thin films of a mixture of PC61BM with the polythiophenes derivatives P1-P4. We prepared two versions of each sample, one including the molecule M1 and another without it. The TA data suggests that the efficiency improvement after addition of M1 is due not only to an extended absorption spectrum towards the infrared region causing a larger population of excitons but also to the possible creation of additional channels for transport of excitons and/or electrons to the PC61BM interface.
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Affiliation(s)
| | | | - R Carriles
- Centro de Investigaciones en Óptica, A.P. 1-948, León, Gto. 37150, Mexico.
| | | | | | - Mario Rodríguez
- Centro de Investigaciones en Óptica, A.P. 1-948, León, Gto. 37150, Mexico.
| | - M Güizado-Rodríguez
- Centro de Investigación en Ingeniería y Ciencias Aplicadas (CIICAp), Universidad Autónoma del Estado de Morelos, Av. Universidad No. 1001, Col. Chamilpa, Cuernavaca, Mor. C.P. 62209, Mexico.
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45
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Plasser F, Wormit M, Dreuw A. New tools for the systematic analysis and visualization of electronic excitations. I. Formalism. J Chem Phys 2015; 141:024106. [PMID: 25027998 DOI: 10.1063/1.4885819] [Citation(s) in RCA: 313] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
A variety of density matrix based methods for the analysis and visualization of electronic excitations are discussed and their implementation within the framework of the algebraic diagrammatic construction of the polarization propagator is reported. Their mathematical expressions are given and an extensive phenomenological discussion is provided to aid the interpretation of the results. Starting from several standard procedures, e.g., population analysis, natural orbital decomposition, and density plotting, we proceed to more advanced concepts of natural transition orbitals and attachment/detachment densities. In addition, special focus is laid on information coded in the transition density matrix and its phenomenological analysis in terms of an electron-hole picture. Taking advantage of both the orbital and real space representations of the density matrices, the physical information in these analysis methods is outlined, and similarities and differences between the approaches are highlighted. Moreover, new analysis tools for excited states are introduced including state averaged natural transition orbitals, which give a compact description of a number of states simultaneously, and natural difference orbitals (defined as the eigenvectors of the difference density matrix), which reveal details about orbital relaxation effects.
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Affiliation(s)
- Felix Plasser
- Interdisciplinary Center for Scientific Computing, Ruprecht-Karls-University, Im Neuenheimer Feld 368, 69120 Heidelberg, Germany
| | - Michael Wormit
- Interdisciplinary Center for Scientific Computing, Ruprecht-Karls-University, Im Neuenheimer Feld 368, 69120 Heidelberg, Germany
| | - Andreas Dreuw
- Interdisciplinary Center for Scientific Computing, Ruprecht-Karls-University, Im Neuenheimer Feld 368, 69120 Heidelberg, Germany
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46
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Ke Y, Liu Y, Zhao Y. Visualization of Hot Exciton Energy Relaxation from Coherent to Diffusive Regimes in Conjugated Polymers: A Theoretical Analysis. J Phys Chem Lett 2015; 6:1741-1747. [PMID: 26263343 DOI: 10.1021/acs.jpclett.5b00490] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The unified coherent-to-diffusive energy relaxation of hot exciton in organic aggregates or polymers, which still remains largely unclear and is also a great challenge theoretically, is investigated from a time-dependent wavepacket diffusive approach. The results demonstrate that in the multiple time scale energy relaxation dynamics, the fast relaxation time essentially corresponds to the dephasing time of excitonic coherence motion, whereas the slow time is related to a hopping migration, and a suggested kinetic model successfully connects these two processes. The dependencies of those times on the initial energy and delocalization of exciton wavepacket as well as exciton-phonon interactions are further analyzed. The proposed method together with quantum chemistry calculations has explained an experimental observation of hot exciton energy relaxation in the low-bandgap copolymer PBDTTPD.
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Affiliation(s)
- Yaling Ke
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, Fujian Provincial Key Lab of Theoretical and Computational Chemistry, and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People's Republic of China
| | - Yuxiu Liu
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, Fujian Provincial Key Lab of Theoretical and Computational Chemistry, and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People's Republic of China
| | - Yi Zhao
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, Fujian Provincial Key Lab of Theoretical and Computational Chemistry, and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People's Republic of China
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47
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Sun N, Zhang X, Deng C. Designed synthesis of MOF-derived magnetic nanoporous carbon materials for selective enrichment of glycans for glycomics analysis. NANOSCALE 2015; 7:6487-6491. [PMID: 25805188 DOI: 10.1039/c5nr00244c] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In this work, magnetic nanoporous carbon (NPC) materials were synthesized by choosing a MOF as a sacrificial template and a carbon precursor. The obtained Co-ZIF-67 materials showed strong magnetic response, high surface area, a uniform size of mesopores and high carbon content. The Co-ZIF-67 materials were successfully applied to glycomics analysis by enriching N-linked glycans in bio-samples with high selectivity and efficiency.
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Affiliation(s)
- Nianrong Sun
- Department of Chemistry and Institutes of Biomedical Sciences, Fudan University, Shanghai, 200433, China.
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48
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Ward AJ, Ruseckas A, Kareem MM, Ebenhoch B, Serrano LA, Al-Eid M, Fitzpatrick B, Rotello VM, Cooke G, Samuel IDW. The impact of driving force on electron transfer rates in photovoltaic donor-acceptor blends. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2015; 27:2496-2500. [PMID: 25759321 DOI: 10.1002/adma.201405623] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 01/24/2015] [Indexed: 06/04/2023]
Abstract
The effect of acceptor energy level on electron transfer rate in blends of the polymer solar-cell material poly[[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl]] (PTB7) is studied using time-resolved fluorescence. Fast electron transfer in less than 2 ps is observed for a driving force between 0.2 and 0.6 eV and the electron transfer is slower outside this range. This dependence is described by Marcus theory with a reorganization energy of ≈0.4 eV.
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Affiliation(s)
- Alexander J Ward
- Organic Semiconductor Centre, SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, Fife, KY16 9SS, UK
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49
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Zhang Q, Zhang Q, Xiong Z, Wan H, Chen X, Zou H. Facile preparation of carbon-functionalized ordered magnetic mesoporous silica composites for highly selective enrichment of N-glycans. RSC Adv 2015. [DOI: 10.1039/c5ra11998g] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A novel carbon-functionalized ordered magnetic mesoporous silica composite was designed and synthesized.
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Affiliation(s)
- Quanqing Zhang
- Division of Metrology in Chemistry
- National Institute of Metrology
- Beijing 100029
- China
- CAS Key Laboratory of Separation Sciences for Analytical Chemistry
| | - Qinghe Zhang
- Division of Metrology in Chemistry
- National Institute of Metrology
- Beijing 100029
- China
| | - Zhichao Xiong
- CAS Key Laboratory of Separation Sciences for Analytical Chemistry
- National Chromatographic R&A Center
- Dalian Institute of Chemical Physics
- Chinese Academy of Sciences (CAS)
- Dalian 116023
| | - Hao Wan
- CAS Key Laboratory of Separation Sciences for Analytical Chemistry
- National Chromatographic R&A Center
- Dalian Institute of Chemical Physics
- Chinese Academy of Sciences (CAS)
- Dalian 116023
| | - Xiaoting Chen
- Division of Metrology in Chemistry
- National Institute of Metrology
- Beijing 100029
- China
| | - Hanfa Zou
- CAS Key Laboratory of Separation Sciences for Analytical Chemistry
- National Chromatographic R&A Center
- Dalian Institute of Chemical Physics
- Chinese Academy of Sciences (CAS)
- Dalian 116023
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50
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Shimazaki T, Nakajima T. Theoretical study of exciton dissociation through hot states at donor–acceptor interface in organic photocell. Phys Chem Chem Phys 2015; 17:12538-44. [DOI: 10.1039/c5cp00740b] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We theoretically study the dissociation of geminate electron–hole pairs (i.e., excitons) through vibrational hot states at the donor–acceptor interface of organic photocells.
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