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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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On the mechanism of vibrational control of light-induced charge transfer in donor–bridge–acceptor assemblies. Nat Chem 2015; 7:689-95. [DOI: 10.1038/nchem.2327] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Accepted: 07/15/2015] [Indexed: 11/08/2022]
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Delor M, Sazanovich IV, Towrie M, Weinstein JA. Probing and Exploiting the Interplay between Nuclear and Electronic Motion in Charge Transfer Processes. Acc Chem Res 2015; 48:1131-9. [PMID: 25789559 DOI: 10.1021/ar500420c] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The Born-Oppenheimer approximation refers to the assumption that the nuclear and electronic wave functions describing a molecular system evolve and can be determined independently. It is now well-known that this approximation often breaks down and that nuclear-electronic (vibronic) coupling contributes greatly to the ultrafast photophysics and photochemistry observed in many systems ranging from simple molecules to biological organisms. In order to probe vibronic coupling in a time-dependent manner, one must use spectroscopic tools capable of correlating the motions of electrons and nuclei on an ultrafast time scale. Recent developments in nonlinear multidimensional electronic and vibrational spectroscopies allow monitoring both electronic and structural factors with unprecedented time and spatial resolution. In this Account, we present recent studies from our group that make use of different variants of frequency-domain transient two-dimensional infrared (T-2DIR) spectroscopy, a pulse sequence combining electronic and vibrational excitations in the form of a UV-visible pump, a narrowband (12 cm(-1)) IR pump, and a broadband (400 cm(-1)) IR probe. In the first example, T-2DIR is used to directly compare vibrational dynamics in the ground and relaxed electronic excited states of Re(Cl)(CO)3(4,4'-diethylester-2,2'-bipyridine) and Ru(4,4'-diethylester-2,2'-bipyridine)2(NCS)2, prototypical charge transfer complexes used in photocatalytic CO2 reduction and electron injection in dye-sensitized solar cells. The experiments show that intramolecular vibrational redistribution (IVR) and vibrational energy transfer (VET) are up to an order of magnitude faster in the triplet charge transfer excited state than in the ground state. These results show the influence of electronic arrangement on vibrational coupling patterns, with direct implications for vibronic coupling mechanisms in charge transfer excited states. In the second example, we show unambiguously that electronic and vibrational movement are coupled in a donor-bridge-acceptor complex based on a Pt(II) trans-acetylide design motif. Time-resolved IR (TRIR) spectroscopy reveals that the rate of electron transfer (ET) is highly dependent on the amount of excess energy localized on the bridge following electronic excitation. Using an adaptation of T-2DIR, we are able to selectively perturb bridge-localized vibrational modes during charge separation, resulting in the donor-acceptor charge separation pathway being completely switched off, with all excess energy redirected toward the formation of a long-lived intraligand triplet state. A series of control experiments reveal that this effect is mode specific: it is only when the high-frequency bridging C≡C stretching mode is pumped that radical changes in photoproduct yields are observed. These experiments therefore suggest that one may perturb electronic movement by stimulating structural motion along the reaction coordinate using IR light. These studies add to a growing body of evidence suggesting that controlling the pathways and efficiency of charge transfer may be achieved through synthetic and perturbative approaches aiming to modulate vibronic coupling. Achieving such control would represent a breakthrough for charge transfer-based applications such as solar energy conversion and molecular electronics.
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Affiliation(s)
- Milan Delor
- Department
of Chemistry, University of Sheffield, Sheffield S3 7HF, U.K
| | - Igor V. Sazanovich
- Central
Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, STFC, Chilton, Oxfordshire OX11 0QX, U.K
| | - Michael Towrie
- Central
Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, STFC, Chilton, Oxfordshire OX11 0QX, U.K
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Delor M, Scattergood PA, Sazanovich IV, Parker AW, Greetham GM, Meijer AJHM, Towrie M, Weinstein JA. Toward control of electron transfer in donor-acceptor molecules by bond-specific infrared excitation. Science 2015; 346:1492-5. [PMID: 25525241 DOI: 10.1126/science.1259995] [Citation(s) in RCA: 125] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Electron transfer (ET) from donor to acceptor is often mediated by nuclear-electronic (vibronic) interactions in molecular bridges. Using an ultrafast electronic-vibrational-vibrational pulse-sequence, we demonstrate how the outcome of light-induced ET can be radically altered by mode-specific infrared (IR) excitation of vibrations that are coupled to the ET pathway. Picosecond narrow-band IR excitation of high-frequency bridge vibrations in an electronically excited covalent trans-acetylide platinum(II) donor-bridge-acceptor system in solution alters both the dynamics and the yields of competing ET pathways, completely switching a charge separation pathway off. These results offer a step toward quantum control of chemical reactivity by IR excitation.
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Affiliation(s)
- Milan Delor
- Department of Chemistry, University of Sheffield, Sheffield S3 7HF, UK
| | | | - Igor V Sazanovich
- Department of Chemistry, University of Sheffield, Sheffield S3 7HF, UK. Central Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Science and Technology Facilities Council, Chilton, Oxfordshire OX11 0QX, UK
| | - Anthony W Parker
- Central Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Science and Technology Facilities Council, Chilton, Oxfordshire OX11 0QX, UK
| | - Gregory M Greetham
- Central Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Science and Technology Facilities Council, Chilton, Oxfordshire OX11 0QX, UK
| | | | - Michael Towrie
- Central Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Science and Technology Facilities Council, Chilton, Oxfordshire OX11 0QX, UK.
| | - Julia A Weinstein
- Department of Chemistry, University of Sheffield, Sheffield S3 7HF, UK.
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Sajeev Y, Moiseyev N. Enhancement of charge transition from donor to acceptor in organic and biochemical reactions by the intermediate-mode-assisted tunneling mechanism. Chem Phys 2010. [DOI: 10.1016/j.chemphys.2010.01.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Weissman S, Peskin U. Coherent site-directed transport in complex molecular networks: an effective Hamiltonian approach. J Chem Phys 2010; 132:114116. [PMID: 20331290 DOI: 10.1063/1.3355550] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Defining the conditions for coherent site-directed transport from an electron donor to a specific acceptor through tunneling barriers in a network of multiple donor/acceptors sites is an important step toward controlling electronic processes in molecular networks. The required analysis is most challenging since the entire network in essentially involved in coherent transport. In this work we introduce an efficient approach for formulating an effective donor/acceptor coupling in terms of the entire network parameters. The approach is based on implementation of Feshbach projection operators to map the entire network Hamiltonian onto a subspace defined by two specific donor and acceptor sites. This nonperturbative approach enables to define regimes of network parameters in which the effective donor-acceptor coupling is optimal. This is demonstrated numerically for simple models of molecular networks.
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Affiliation(s)
- Shira Weissman
- Schulich Faculty of Chemistry and The Lise Meitner Center for Computational Quantum Chemistry, Technion-Israel Institute of Technology, Haifa 32000, Israel
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