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Li J, Ji Q, Wang R, Zhang ZG, Wang X, Xiao M, Lu YQ, Zhang C. Charge Generation Dynamics in Organic Photovoltaic Blends under One-Sun-Equivalent Illumination Detected by Highly Sensitive Terahertz Spectroscopy. J Am Chem Soc 2024; 146:20312-20322. [PMID: 38980945 DOI: 10.1021/jacs.4c05786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/11/2024]
Abstract
Organic photovoltaic (OPV) devices attain high performance with nonfullerene acceptors by utilizing the synergistic dual channels of charge generation that originate from excitations in both the donor and acceptor materials. However, the specific intermediate states that facilitate both channels are subject to debate. To address this issue, we employ time-resolved terahertz spectroscopy with improved sensitivity (ΔE/E < 10-6), enabling direct probing of charge generation dynamics in a prototypical PM6:Y6 bulk heterojunction system under one-sun-equivalent excitation density. Charge generation arising from donor excitations is characterized with a rise time of ∼9 ps, while that from acceptor excitations shows a rise time of ∼18 ps. Temperature-dependent measurements further reveal notably distinct activation energies for these two charge generation pathways. Additionally, the two channels of charge generation can be substantially manipulated by altering the ratio of bulk to interfaces. These findings strongly suggest the presence of two distinct intermediate states: interfacial and intramoiety excitations. These states are crucial in mediating the transfer of electrons and holes, driving charge generation within OPV devices.
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Affiliation(s)
- Jiacong Li
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center for Advanced Microstructures, Nanjing University, Nanjing 210093, China
| | - Qing Ji
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center for Advanced Microstructures, Nanjing University, Nanjing 210093, China
| | - Rui Wang
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center for Advanced Microstructures, Nanjing University, Nanjing 210093, China
- College of Physics, Nanjing University of Aeronautics and Astronautics, and Key Laboratory of Aerospace Information Materials and Physics (NUAA), MIIT, Nanjing 211106, China
- Institute of Materials Engineering, Nanjing University, Nantong, Jiangsu 226019, China
| | - Zhi-Guo Zhang
- State Key Laboratory of Organic/Inorganic Composites, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Xiaoyong Wang
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center for Advanced Microstructures, Nanjing University, Nanjing 210093, China
| | - Min Xiao
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center for Advanced Microstructures, Nanjing University, Nanjing 210093, China
- Department of Physics, University of Arkansas, Fayetteville, Arkansas 72701, United States
| | - Yan-Qing Lu
- National Laboratory of Solid State Microstructures, Key Laboratory of Intelligent Optical Sensing and Manipulation, College of Engineering and Applied Sciences, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210023, China
| | - Chunfeng Zhang
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center for Advanced Microstructures, Nanjing University, Nanjing 210093, China
- Institute of Materials Engineering, Nanjing University, Nantong, Jiangsu 226019, China
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Affiliation(s)
- Ayesha Kausar
- Nanosciences Division, National Center For Physics, Quaid-i-Azam University Campus, Islamabad, Pakistan
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3
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Melianas A, Kemerink M. Photogenerated Charge Transport in Organic Electronic Materials: Experiments Confirmed by Simulations. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1806004. [PMID: 30719756 DOI: 10.1002/adma.201806004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Revised: 10/29/2018] [Indexed: 06/09/2023]
Abstract
The performance of organic optoelectronic devices, such as organic photovoltaic (OPV) cells, is to a large extent dictated by their ability to transport the photogenerated charge, with relevant processes spanning a wide temporal (fs-µs) and spatial (1-100 nm) range. However, time-resolved techniques can access only a limited temporal window, and often contradict steady-state measurements. Here, commonly employed steady-state and time-resolved techniques are unified over an exceptionally wide temporal range (fs-µs) in a consistent physical picture. Experimental evidence confirmed by numerical simulations shows that, although various techniques probe different time scales, they are mutually consistent as they probe the same physical mechanisms governing charge motion in disordered media-carrier hopping and thermalization in a disorder-broadened density of states (DOS). The generality of this framework is highlighted by time-resolved experimental data obtained on polymer:fullerene, polymer:polymer, and small-molecule blends with varying morphology, including recent experiments revealing that low donor content OPV devices operate by long-range hole tunneling between non-nearest-neighbor molecules. The importance of nonequilibrium processes in organic electronic materials is reviewed, with a particular focus on experimental data and understanding charge transport physics in terms of material DOS.
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Affiliation(s)
- Armantas Melianas
- Department of Materials Science and Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Martijn Kemerink
- Complex Materials and Devices, Department of Physics, Chemistry and Biology, Linköping University, 58183, Linköping, Sweden
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4
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Eckstein A, Bertašius V, Jašinskas V, Namal I, Hertel T, Gulbinas V. Carrier photogeneration, drift and recombination in a semiconducting carbon nanotube network. NANOSCALE 2017; 9:12441-12448. [PMID: 28809414 DOI: 10.1039/c7nr03813e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Charge carrier photogeneration, drift and recombination in thin film networks of polymer-wrapped (6,5)-single-wall carbon nanotubes (SWNTs) blended with phenyl-C61-butyric acid methyl ester (PCBM) have been investigated by using transient photocurrent and time-delayed collection field (TDCF) techniques. Three distinct transient photocurrent components on the nano- and microsecond timescales have been identified. We attribute the dominant (>50% of total extracted charge) ultrashort photocurrent component with a decay time below our experimental time-resolution of 2 ns to the intratube hole motion. The second component on the few microsecond timescale is attributed to the intertube hole transfer, while the slowest component is assigned to the electron drift within the PCBM phase. The hole drift distance appears to be limited by gaps in the nanotube percolation network rather than by hole trapping or recombination. Photocurrent saturation was observed when excitation densities reached more than one charge pair per nanotube; we attribute this to the local electric field screening.
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Affiliation(s)
- A Eckstein
- Center for Physical Sciences and Technology, Saulėtekio av. 3, LT-10257 Vilnius, Lithuania.
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5
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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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6
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Corani A, Li MH, Shen PS, Chen P, Guo TF, El Nahhas A, Zheng K, Yartsev A, Sundström V, Ponseca CS. Ultrafast Dynamics of Hole Injection and Recombination in Organometal Halide Perovskite Using Nickel Oxide as p-Type Contact Electrode. J Phys Chem Lett 2016; 7:1096-101. [PMID: 26942559 DOI: 10.1021/acs.jpclett.6b00238] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
There is a mounting effort to use nickel oxide (NiO) as p-type selective electrode for organometal halide perovskite-based solar cells. Recently, an overall power conversion efficiency using this hole acceptor has reached 18%. However, ultrafast spectroscopic investigations on the mechanism of charge injection as well as recombination dynamics have yet to be studied and understood. Using time-resolved terahertz spectroscopy, we show that hole transfer is complete on the subpicosecond time scale, driven by the favorable band alignment between the valence bands of perovskite and NiO nanoparticles (NiO(np)). Recombination time between holes injected into NiO(np) and mobile electrons in the perovskite material is shown to be hundreds of picoseconds to a few nanoseconds. Because of the low conductivity of NiO(np), holes are pinned at the interface, and it is electrons that determine the recombination rate. This recombination competes with charge collection and therefore must be minimized. Doping NiO to promote higher mobility of holes is desirable in order to prevent back recombination.
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Affiliation(s)
- Alice Corani
- Division of Chemical Physics, Lund University , Box 124, 221 00 Lund, Sweden
| | - Ming-Hsien Li
- Department of Photonics, National Cheng Kung University , Tainan, Taiwan 701
| | - Po-Shen Shen
- Department of Photonics, National Cheng Kung University , Tainan, Taiwan 701
| | - Peter Chen
- Department of Photonics, National Cheng Kung University , Tainan, Taiwan 701
- Research Center for Energy Technology and Strategy (RCETS), Tainan, Taiwan 701
- Advanced Optoelectronic Technology Center (AOTC), Tainan, Taiwan 701
| | - Tzung-Fang Guo
- Department of Photonics, National Cheng Kung University , Tainan, Taiwan 701
- Research Center for Energy Technology and Strategy (RCETS), Tainan, Taiwan 701
- Advanced Optoelectronic Technology Center (AOTC), Tainan, Taiwan 701
| | - Amal El Nahhas
- Division of Chemical Physics, Lund University , Box 124, 221 00 Lund, Sweden
| | - Kaibo Zheng
- Division of Chemical Physics, Lund University , Box 124, 221 00 Lund, Sweden
| | - Arkady Yartsev
- Division of Chemical Physics, Lund University , Box 124, 221 00 Lund, Sweden
| | - Villy Sundström
- Division of Chemical Physics, Lund University , Box 124, 221 00 Lund, Sweden
| | - Carlito S Ponseca
- Division of Chemical Physics, Lund University , Box 124, 221 00 Lund, Sweden
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7
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Ponseca CS, Sundström V. Revealing the ultrafast charge carrier dynamics in organo metal halide perovskite solar cell materials using time resolved THz spectroscopy. NANOSCALE 2016; 8:6249-6257. [PMID: 26763720 DOI: 10.1039/c5nr08622a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Ultrafast charge carrier dynamics in organo metal halide perovskite has been probed using time resolved terahertz (THz) spectroscopy (TRTS). Current literature on its early time characteristics is unanimous: sub-ps charge carrier generation, highly mobile charges and very slow recombination rationalizing the exceptionally high power conversion efficiency for a solution processed solar cell material. Electron injection from MAPbI3 to nanoparticles (NP) of TiO2 is found to be sub-ps while Al2O3 NPs do not alter charge dynamics. Charge transfer to organic electrodes, Spiro-OMeTAD and PCBM, is sub-ps and few hundreds of ps respectively, which is influenced by the alignment of energy bands. It is surmised that minimizing defects/trap states is key in optimizing charge carrier extraction from these materials.
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Affiliation(s)
- C S Ponseca
- Division of Chemical Physics, Lund University, Getingevagen 60, Lund, Sweden.
| | - V Sundström
- Division of Chemical Physics, Lund University, Getingevagen 60, Lund, Sweden.
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Ponseca CS, Tian Y, Sundström V, Scheblykin IG. Excited state and charge-carrier dynamics in perovskite solar cell materials. NANOTECHNOLOGY 2016; 27:082001. [PMID: 26820442 DOI: 10.1088/0957-4484/27/8/082001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Organo-metal halide perovskites (OMHPs) have attracted enormous interest in recent years as materials for application in optoelectronics and solar energy conversion. These hybrid semiconductors seem to have the potential to challenge traditional silicon technology. In this review we will give an account of the recent development in the understanding of the fundamental light-induced processes in OMHPs from charge-photo generation, migration of charge carries through the materials and finally their recombination. Our and other literature reports on time-resolved conductivity, transient absorption and photoluminescence properties are used to paint a picture of how we currently see the fundamental excited state and charge-carrier dynamics. We will also show that there is still no fully coherent picture of the processes in OMHPs and we will indicate the problems to be solved by future research.
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9
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Fusco S, Maglione C, Velardo A, Piccialli V, Liguori R, Peluso A, Rubino A, Centore R. N-Rich Fused Heterocyclic Systems: Synthesis, Structure, Optical and Electrochemical Characterization. European J Org Chem 2016. [DOI: 10.1002/ejoc.201501283] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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10
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Melianas A, Etzold F, Savenije TJ, Laquai F, Inganäs O, Kemerink M. Photo-generated carriers lose energy during extraction from polymer-fullerene solar cells. Nat Commun 2015; 6:8778. [PMID: 26537357 PMCID: PMC4659933 DOI: 10.1038/ncomms9778] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 10/01/2015] [Indexed: 11/23/2022] Open
Abstract
In photovoltaic devices, the photo-generated charge carriers are typically assumed to be in thermal equilibrium with the lattice. In conventional materials, this assumption is experimentally justified as carrier thermalization completes before any significant carrier transport has occurred. Here, we demonstrate by unifying time-resolved optical and electrical experiments and Monte Carlo simulations over an exceptionally wide dynamic range that in the case of organic photovoltaic devices, this assumption is invalid. As the photo-generated carriers are transported to the electrodes, a substantial amount of their energy is lost by continuous thermalization in the disorder broadened density of states. Since thermalization occurs downward in energy, carrier motion is boosted by this process, leading to a time-dependent carrier mobility as confirmed by direct experiments. We identify the time and distance scales relevant for carrier extraction and show that the photo-generated carriers are extracted from the operating device before reaching thermal equilibrium.
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Affiliation(s)
- Armantas Melianas
- Biomolecular and Organic Electronics, Department of Physics, Chemistry and Biology, Linköping University, 58183 Linköping, Sweden
| | - Fabian Etzold
- Max Planck Research Group for Organic Optoelectronics, Max Planck Institute for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
| | - Tom J. Savenije
- Optoelectronic Materials Section, Department of Chemical Engineering, Delft University of Technology, 2628 BL Delft, The Netherlands
| | - Frédéric Laquai
- Max Planck Research Group for Organic Optoelectronics, Max Planck Institute for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
- Physical Sciences and Engineering Division, Material Science and Engineering, Solar and Photovoltaics Engineering Research Center, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Olle Inganäs
- Biomolecular and Organic Electronics, Department of Physics, Chemistry and Biology, Linköping University, 58183 Linköping, Sweden
| | - Martijn Kemerink
- Complex Materials and Devices, Department of Physics, Chemistry and Biology, Linköping University, 58183 Linköping, Sweden
- Department of Applied Physics, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven, The Netherlands
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11
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Jin Z, Gehrig D, Dyer-Smith C, Heilweil EJ, Laquai F, Bonn M, Turchinovich D. Ultrafast Terahertz Photoconductivity of Photovoltaic Polymer-Fullerene Blends: A Comparative Study Correlated with Photovoltaic Device Performance. J Phys Chem Lett 2014; 5:3662-3668. [PMID: 26278734 DOI: 10.1021/jz501890n] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Ultrafast photoinduced carrier dynamics in prototypical low band gap polymer:fullerene photovoltaic blend films PTB7:PC70BM and P3HT:PC70BM is investigated using ultrafast terahertz (THz) spectroscopy. The subpicosecond and few-picosecond decays of THz-probed photoconductivities for both compounds are observed, attributed to the rapid formation of polaron pairs by exciton-exciton annihilation and subsequent polaron pair annihilation, respectively. The transient THz photoconductivity spectra of PTB7:PC70BM are well described by the Drude-Smith (DS) model, directly yielding the important charge transport parameters such as charge carrier density, momentum scattering time, and effective localization. By comparison with P3HT:PC70BM, we find that in PTB7:PC70BM the mobile charge carrier photoconductivity is significantly enhanced by a factor of 1.8 and prevails for longer times after charge formation, due to both improved mobile charge carrier yield and lower charge localization. In PTB7:PC70BM, a strong dependency of electron momentum scattering time on electron density was found, well parametrized by the empirical Caughey-Thomas model. The difference in ultrafast photoconductivities of both P3HT:PC70BM and PTB7:PC70BM is found to correlate very well with the performance of photovoltaic devices based on those materials.
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Affiliation(s)
- Zuanming Jin
- †Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Dominik Gehrig
- †Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Clare Dyer-Smith
- †Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Edwin J Heilweil
- ‡NIST - National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899, United States
| | - Frédéric Laquai
- †Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Mischa Bonn
- †Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Dmitry Turchinovich
- †Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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12
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Abramavičius V, Amarasinghe Vithanage D, Devižis A, Infahsaeng Y, Bruno A, Foster S, Keivanidis PE, Abramavičius D, Nelson J, Yartsev A, Sundström V, Gulbinas V. Carrier motion in as-spun and annealed P3HT:PCBM blends revealed by ultrafast optical electric field probing and Monte Carlo simulations. Phys Chem Chem Phys 2014; 16:2686-92. [PMID: 24384829 DOI: 10.1039/c3cp54605e] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Charge transport dynamics in solar cell devices based on as-spun and annealed P3HT:PCBM films are compared using ultrafast time-resolved optical probing of the electric field by means of field-induced second harmonic generation. The results show that charge carriers drift about twice as far during the first 3 ns after photogeneration in a device where the active layer has been thermally annealed. The carrier dynamics were modelled using Monte-Carlo simulations and good agreement between experimental and simulated drift dynamics was obtained using identical model parameters for both cells, but with different average PCBM and polymer domain sizes. The calculations suggest that small domain sizes in as-spun samples limit the carrier separation distance disabling their escape from geminate recombination.
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Affiliation(s)
- Vytautas Abramavičius
- Center for Physical Sciences and Technology, Savanoriu 231, LT-02300 Vilnius, Lithuania
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13
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Pranculis V, Infahsaeng Y, Tang Z, Devižis A, Vithanage DA, Ponseca CS, Inganäs O, Yartsev AP, Gulbinas V, Sundström V. Charge carrier generation and transport in different stoichiometry APFO3:PC61BM solar cells. J Am Chem Soc 2014; 136:11331-8. [PMID: 25025885 DOI: 10.1021/ja503301m] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
In this paper we studied carrier drift dynamics in APFO3:PC61BM solar cells of varied stoichiometry (2:1, 1:1, and 1:4 APFO3:PC61BM) over a wide time range, from subpicoseconds to microseconds with a combination of ultrafast optical electric field probing and conventional transient integrated photocurrent techniques. Carrier drift and extraction dynamics are strongly stoichiometry dependent: the speed of electron or hole drift increases with higher concentration of PC61BM or polymer, respectively. The electron extraction from a sample with 80% PC61BM takes place during hundreds of picoseconds, but slows down to sub-microseconds in a sample with 33% PC61BM. The hole extraction is less stoichiometry dependent: it varies form sub-nanoseconds to tens of nanoseconds when the PC61BM concentration changes from 33% to 80%. The electron extraction rate correlates with the conversion efficiency of solar cells, leading to the conclusion that fast electron motion is essential for efficient charge carrier separation preventing their geminate recombination.
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Affiliation(s)
- Vytenis Pranculis
- Center for Physical Sciences and Technology , Savanoriu 231, LT-02300 Vilnius, Lithuania
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14
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Amarasinghe Vithanage D, Devižis A, Abramavičius V, Infahsaeng Y, Abramavičius D, MacKenzie RCI, Keivanidis PE, Yartsev A, Hertel D, Nelson J, Sundström V, Gulbinas V. Visualizing charge separation in bulk heterojunction organic solar cells. Nat Commun 2014; 4:2334. [PMID: 23945881 DOI: 10.1038/ncomms3334] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Accepted: 07/22/2013] [Indexed: 11/09/2022] Open
Abstract
Solar cells based on conjugated polymer and fullerene blends have been developed as a low-cost alternative to silicon. For efficient solar cells, electron-hole pairs must separate into free mobile charges that can be extracted in high yield. We still lack good understanding of how, why and when carriers separate against the Coulomb attraction. Here we visualize the charge separation process in bulk heterojunction solar cells by directly measuring charge carrier drift in a polymer:fullerene blend with ultrafast time resolution. We show that initially only closely separated (<1 nm) charge pairs are created and they separate by several nanometres during the first several picoseconds. Charge pairs overcome Coulomb attraction and form free carriers on a subnanosecond time scale. Numerical simulations complementing the experimental data show that fast three-dimensional charge diffusion within an energetically disordered medium, increasing the entropy of the system, is sufficient to drive the charge separation process.
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15
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Ponseca CS, Savenije TJ, Abdellah M, Zheng K, Yartsev A, Pascher T, Harlang T, Chabera P, Pullerits T, Stepanov A, Wolf JP, Sundström V. Organometal Halide Perovskite Solar Cell Materials Rationalized: Ultrafast Charge Generation, High and Microsecond-Long Balanced Mobilities, and Slow Recombination. J Am Chem Soc 2014; 136:5189-92. [DOI: 10.1021/ja412583t] [Citation(s) in RCA: 977] [Impact Index Per Article: 97.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Carlito S. Ponseca
- Division
of Chemical Physics, Lund University, Box 124, 221 00 Lund, Sweden
| | - Tom J. Savenije
- Department
of Chemical Engineering, Delft University of Technology, 2628 BL Delft, The Netherlands
| | - Mohamed Abdellah
- Division
of Chemical Physics, Lund University, Box 124, 221 00 Lund, Sweden
- Department
of Chemistry, Qena Faculty of Science, South Valley University, Qena 83523, Egypt
| | - Kaibo Zheng
- Division
of Chemical Physics, Lund University, Box 124, 221 00 Lund, Sweden
| | - Arkady Yartsev
- Division
of Chemical Physics, Lund University, Box 124, 221 00 Lund, Sweden
| | - Tobjörn Pascher
- Division
of Chemical Physics, Lund University, Box 124, 221 00 Lund, Sweden
| | - Tobias Harlang
- Division
of Chemical Physics, Lund University, Box 124, 221 00 Lund, Sweden
| | - Pavel Chabera
- Division
of Chemical Physics, Lund University, Box 124, 221 00 Lund, Sweden
| | - Tonu Pullerits
- Division
of Chemical Physics, Lund University, Box 124, 221 00 Lund, Sweden
| | - Andrey Stepanov
- GAP-Biophotonics, University of Geneva, 1211 Geneva 4, Switzerland
| | - Jean-Pierre Wolf
- GAP-Biophotonics, University of Geneva, 1211 Geneva 4, Switzerland
| | - Villy Sundström
- Division
of Chemical Physics, Lund University, Box 124, 221 00 Lund, Sweden
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16
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Vukmirović N. A comparative study of electronic properties of disordered conjugated polymers. Phys Chem Chem Phys 2013; 15:3543-51. [DOI: 10.1039/c3cp43115k] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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