1
|
Shoaee S, Luong HM, Song J, Zou Y, Nguyen TQ, Neher D. What We have Learnt from PM6:Y6. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2302005. [PMID: 37623325 DOI: 10.1002/adma.202302005] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 07/10/2023] [Indexed: 08/26/2023]
Abstract
Over the past three years, remarkable advancements in organic solar cells (OSCs) have emerged, propelled by the introduction of Y6-an innovative A-DA'D-A type small molecule non-fullerene acceptor (NFA). This review provides a critical discussion of the current knowledge about the structural and physical properties of the PM6:Y6 material combination in relation to its photovoltaic performance. The design principles of PM6 and Y6 are discussed, covering charge transfer, transport, and recombination mechanisms. Then, the authors delve into blend morphology and degradation mechanisms before considering commercialization. The current state of the art is presented, while also discussing unresolved contentious issues, such as the blend energetics, the pathways of free charge generation, and the role of triplet states in recombination. As such, this review aims to provide a comprehensive understanding of the PM6:Y6 material combination and its potential for further development in the field of organic solar cells. By addressing both the successes and challenges associated with this system, this review contributes to the ongoing research efforts toward achieving more efficient and stable organic solar cells.
Collapse
Affiliation(s)
- Safa Shoaee
- Optoelectronics of Disordered Semiconductors, Institute of Physics and Astronomy, University of Potsdam, D-14476, Potsdam-Golm, Germany
- Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e.V., 10117, Berlin, Germany
| | - Hoang M Luong
- Centre for Polymers and Organic Solids, University of California, Santa Barbara, CA, 93106, USA
| | - Jiage Song
- College of Chemistry and Chemical Engineering, Central South University, Changsha, 410083, P. R. China
| | - Yingping Zou
- College of Chemistry and Chemical Engineering, Central South University, Changsha, 410083, P. R. China
| | - Thuc-Quyen Nguyen
- Centre for Polymers and Organic Solids, University of California, Santa Barbara, CA, 93106, USA
| | - Dieter Neher
- Soft Matter Physics and Optoelectronics, Institute of Physics and Astronomy, University of Potsdam, D-14476, Potsdam-Golm, Germany
| |
Collapse
|
2
|
Korte D, Pavlica E, Klančar D, Bratina G, Pawlak M, Gondek E, Song P, Liu J, Derkowska-Zielinska B. Influence of P3HT:PCBM Ratio on Thermal and Transport Properties of Bulk Heterojunction Solar Cells. MATERIALS (BASEL, SWITZERLAND) 2023; 16:617. [PMID: 36676353 PMCID: PMC9861154 DOI: 10.3390/ma16020617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 01/02/2023] [Accepted: 01/04/2023] [Indexed: 06/17/2023]
Abstract
The influence of P3HT:PCBM ratio on thermal and transport properties of solar cells were determined by photothermal beam deflection spectrometry, which is advantageous tool for non-destructively study of bulk heterojunction layers of organic solar cells. P3HT:PCBM layers of different P3HT:PCBM ratios were deposited on top of PEDOT:PSS/ITO layers which were included in organic bulk-heterojunction solar cells. The thermal diffusivity, energy gap and charge carrier lifetime were measured at different illumination conditions and with a different P3HT:PCBM ratios. As expected, it was found that the energy band gap depends on the P3HT:PCBM ratio. Thermal diffusivity is decreasing, while charge carrier lifetime is increasing with PCBM concentration. Energy band gap was found to be independent on illumination intensity, while thermal diffusivity was increasing and carrier lifetime was decreasing with illumination intensity. The carrier lifetime exhibits qualitatively similar dependence on the PCBM concentration when compared to the open-circuit voltage of operating solar cells under AM1.5 illumination. BDS and standard I-V measurement yielded comparable results arguing that the former is suitable for characterization of organic solar cells.
Collapse
Affiliation(s)
- Dorota Korte
- Laboratory for Environmental and Life Sciences, University of Nova Gorica, Vipavska 13, SI-5000 Nova Gorica, Slovenia
| | - Egon Pavlica
- Laboratory for Organic Matter Physics, University of Nova Gorica, Vipavska 13, SI-5000 Nova Gorica, Slovenia
| | - Domen Klančar
- Laboratory for Organic Matter Physics, University of Nova Gorica, Vipavska 13, SI-5000 Nova Gorica, Slovenia
| | - Gvido Bratina
- Laboratory for Organic Matter Physics, University of Nova Gorica, Vipavska 13, SI-5000 Nova Gorica, Slovenia
| | - Michal Pawlak
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, 87-100 Torun, Poland
| | - Ewa Gondek
- Institute of Physics, Cracow University of Technology, 30-084 Kraków, Poland
| | - Peng Song
- State Key Laboratory of Robotics and System, Harbin Institute of Technology, Harbin 150001, China
- School of Instrumentation Science and Engineering, Harbin Institute of Technology, Harbin 150001, China
| | - Junyan Liu
- School of Instrumentation Science and Engineering, Harbin Institute of Technology, Harbin 150001, China
- School of Mechatronics Engineering, Harbin Institute of Technology, Harbin 150001, China
| | - Beata Derkowska-Zielinska
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, 87-100 Torun, Poland
| |
Collapse
|
3
|
Zeiske S, Sandberg OJ, Kurpiers J, Shoaee S, Meredith P, Armin A. Probing Charge Generation Efficiency in Thin-Film Solar Cells by Integral-Mode Transient Charge Extraction. ACS PHOTONICS 2022; 9:1188-1195. [PMID: 35571262 PMCID: PMC9097587 DOI: 10.1021/acsphotonics.1c01532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Indexed: 06/15/2023]
Abstract
The photogeneration of free charges in light-harvesting devices is a multistep process, which can be challenging to probe due to the complexity of contributing energetic states and the competitive character of different driving mechanisms. In this contribution, we advance a technique, integral-mode transient charge extraction (ITCE), to probe these processes in thin-film solar cells. ITCE combines capacitance measurements with the integral-mode time-of-flight method in the low intensity regime of sandwich-type thin-film devices and allows for the sensitive determination of photogenerated charge-carrier densities. We verify the theoretical framework of our method by drift-diffusion simulations and demonstrate the applicability of ITCE to organic and perovskite semiconductor-based thin-film solar cells. Furthermore, we examine the field dependence of charge generation efficiency and find our ITCE results to be in excellent agreement with those obtained via time-delayed collection field measurements conducted on the same devices.
Collapse
Affiliation(s)
- Stefan Zeiske
- Sustainable
Advanced Materials (Sêr-SAM), Department of Physics, Swansea University, Singleton Park, Swansea SA2 8PP, Wales, United Kingdom
| | - Oskar J. Sandberg
- Sustainable
Advanced Materials (Sêr-SAM), Department of Physics, Swansea University, Singleton Park, Swansea SA2 8PP, Wales, United Kingdom
| | - Jona Kurpiers
- Disordered Semiconductor Optoelectronics,
Institute
of Physics and Astronomy, University Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam-Golm, Germany
| | - Safa Shoaee
- Disordered Semiconductor Optoelectronics,
Institute
of Physics and Astronomy, University Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam-Golm, Germany
| | - Paul Meredith
- Sustainable
Advanced Materials (Sêr-SAM), Department of Physics, Swansea University, Singleton Park, Swansea SA2 8PP, Wales, United Kingdom
| | - Ardalan Armin
- Sustainable
Advanced Materials (Sêr-SAM), Department of Physics, Swansea University, Singleton Park, Swansea SA2 8PP, Wales, United Kingdom
| |
Collapse
|
4
|
Nanayakkara MPA, Masteghin MG, Basiricò L, Fratelli I, Ciavatti A, Kilbride RC, Jenatsch S, Webb T, Richheimer F, Wood S, Castro FA, Parnell AJ, Fraboni B, Jayawardena KDGI, Silva SRP. Molecular Weight Tuning of Organic Semiconductors for Curved Organic-Inorganic Hybrid X-Ray Detectors. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2101746. [PMID: 34755497 PMCID: PMC8805550 DOI: 10.1002/advs.202101746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 07/31/2021] [Indexed: 06/13/2023]
Abstract
Curved X-ray detectors have the potential to revolutionize diverse sectors due to benefits such as reduced image distortion and vignetting compared to their planar counterparts. While the use of inorganic semiconductors for curved detectors are restricted by their brittle nature, organic-inorganic hybrid semiconductors which incorporated bismuth oxide nanoparticles in an organic bulk heterojunction consisting of poly(3-hexylthiophene-2,5-diyl) (P3HT) and [6,6]-phenyl C71 butyric acid methyl ester (PC70 BM) are considered to be more promising in this regard. However, the influence of the P3HT molecular weight on the mechanical stability of curved, thick X-ray detectors remains less well understood. Herein, high P3HT molecular weights (>40 kDa) are identified to allow increased intermolecular bonding and chain entanglements, resulting in X-ray detectors that can be curved to a radius as low as 1.3 mm with low deviation in X-ray response under 100 repeated bending cycles while maintaining an industry-standard dark current of <1 pA mm-2 and a sensitivity of ≈ 0.17 μC Gy-1 cm-2 . This study identifies a crucial missing link in the development of curved detectors, namely the importance of the molecular weight of the polymer semiconductors used.
Collapse
Affiliation(s)
- M. Prabodhi A. Nanayakkara
- Advanced Technology InstituteDepartment of Electrical and Electronic EngineeringUniversity of SurreyGuildfordSurreyGU2 7XHUK
| | - Mateus G. Masteghin
- Advanced Technology InstituteDepartment of Electrical and Electronic EngineeringUniversity of SurreyGuildfordSurreyGU2 7XHUK
| | - Laura Basiricò
- Department of Physics and AstronomyUniversity of BolognaViale Berti Pichat 6/2Bologna40127Italy
- National Institute for Nuclear PhysicsINFN section of BolognaBologna40127Italy
| | - Ilaria Fratelli
- Department of Physics and AstronomyUniversity of BolognaViale Berti Pichat 6/2Bologna40127Italy
- National Institute for Nuclear PhysicsINFN section of BolognaBologna40127Italy
| | - Andrea Ciavatti
- Department of Physics and AstronomyUniversity of BolognaViale Berti Pichat 6/2Bologna40127Italy
- National Institute for Nuclear PhysicsINFN section of BolognaBologna40127Italy
| | - Rachel C. Kilbride
- Department of Physics and AstronomyUniversity of SheffieldHicks BuildingSheffieldS3 7RHUK
| | | | - Thomas Webb
- Advanced Technology InstituteDepartment of Electrical and Electronic EngineeringUniversity of SurreyGuildfordSurreyGU2 7XHUK
| | | | - Sebastian Wood
- National Physical LaboratoryTeddingtonMiddlesexTW11 0LWUK
| | | | - Andrew J. Parnell
- Department of Physics and AstronomyUniversity of SheffieldHicks BuildingSheffieldS3 7RHUK
| | - Beatrice Fraboni
- Department of Physics and AstronomyUniversity of BolognaViale Berti Pichat 6/2Bologna40127Italy
- National Institute for Nuclear PhysicsINFN section of BolognaBologna40127Italy
| | - K. D. G. Imalka Jayawardena
- Advanced Technology InstituteDepartment of Electrical and Electronic EngineeringUniversity of SurreyGuildfordSurreyGU2 7XHUK
| | - S. Ravi P. Silva
- Advanced Technology InstituteDepartment of Electrical and Electronic EngineeringUniversity of SurreyGuildfordSurreyGU2 7XHUK
| |
Collapse
|
5
|
Huang Y, Elder DL, Kwiram AL, Jenekhe SA, Jen AKY, Dalton LR, Luscombe CK. Organic Semiconductors at the University of Washington: Advancements in Materials Design and Synthesis and toward Industrial Scale Production. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e1904239. [PMID: 31576634 DOI: 10.1002/adma.201904239] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 09/07/2019] [Indexed: 06/10/2023]
Abstract
Research at the University of Washington regarding organic semiconductors is reviewed, covering four major topics: electro-optics, organic light emitting diodes, organic field-effect transistors, and organic solar cells. Underlying principles of materials design are demonstrated along with efforts toward unlocking the full potential of organic semiconductors. Finally, opinions on future research directions are presented, with a focus on commercial competency, environmental sustainability, and scalability of organic-semiconductor-based devices.
Collapse
Affiliation(s)
- Yunping Huang
- Materials Science and Engineering Department, University of Washington, Seattle, WA, 98195, USA
| | - Delwin L Elder
- Department of Chemistry, University of Washington, Seattle, WA, 98195, USA
| | - Alvin L Kwiram
- Department of Chemistry, University of Washington, Seattle, WA, 98195, USA
| | - Samson A Jenekhe
- Department of Chemistry, University of Washington, Seattle, WA, 98195, USA
- Department of Chemical Engineering, University of Washington, Seattle, WA, 98195, USA
| | - Alex K Y Jen
- Department of Materials Science and Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Larry R Dalton
- Department of Chemistry, University of Washington, Seattle, WA, 98195, USA
| | - Christine K Luscombe
- Materials Science and Engineering Department, University of Washington, Seattle, WA, 98195, USA
- Department of Chemistry, University of Washington, Seattle, WA, 98195, USA
| |
Collapse
|
6
|
Mechanistic insights on improved performance of PCDTBT:PC71BM hetero-structured organic photovoltaic cells via interfacing CdSe/ZnS nanostructures. APPLIED NANOSCIENCE 2021. [DOI: 10.1007/s13204-021-01789-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
7
|
Cai Y, Zhang H, Ye L, Zhang R, Xu J, Zhang K, Bi P, Li T, Weng K, Xu K, Xia J, Bao Q, Liu F, Hao X, Tan S, Gao F, Zhan X, Sun Y. Effect of the Energy Offset on the Charge Dynamics in Nonfullerene Organic Solar Cells. ACS APPLIED MATERIALS & INTERFACES 2020; 12:43984-43991. [PMID: 32885945 DOI: 10.1021/acsami.0c13085] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The energy offset, considered as the driving force for charge transfer between organic molecules, has significant effects on both charge separation and charge recombination in organic solar cells. Herein, we designed material systems with gradually shifting energy offsets, including both positive and negative values. Time-resolved spectroscopy was used to monitor the charge dynamics within the bulk heterojunction. It is striking to find that there is still charge transfer and charge generation when the energy offset reached -0.10 eV (ultraviolet photoelectron spectroscopy data). This work not only indicates the feasibility of the free carrier generation and the following charge separation under the condition of a negative offset but also elucidates the relationship between the charge transfer and the energy offset in the case of polymer chlorination.
Collapse
Affiliation(s)
- Yunhao Cai
- School of Chemistry, Beihang University, Beijing 100191, P. R. China
| | - Huotian Zhang
- Department of Physics, Chemistry, and Biology, Linköping University, Linköping 58183, Sweden
| | - Linglong Ye
- School of Chemistry, Beihang University, Beijing 100191, P. R. China
| | - Rui Zhang
- Department of Physics, Chemistry, and Biology, Linköping University, Linköping 58183, Sweden
| | - Jinqiu Xu
- School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai 200240, P. R. China
| | - Kangning Zhang
- School of Physics State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, P. R. China
| | - Pengqing Bi
- School of Physics State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, P. R. China
| | - Tengfei Li
- Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing 100871, P. R. China
| | - Kangkang Weng
- School of Chemistry, Beihang University, Beijing 100191, P. R. China
| | - Ke Xu
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Center of Smart Materials and Devices, Wuhan University of Technology, Wuhan 430070, P. R. China
| | - Jianlong Xia
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Center of Smart Materials and Devices, Wuhan University of Technology, Wuhan 430070, P. R. China
| | - Qinye Bao
- Key Laboratory of Polar Materials and Devices, Department of Optoelectronics, East China Normal University, 200241 Shanghai, P. R. China
| | - Feng Liu
- School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai 200240, P. R. China
| | - Xiaotao Hao
- School of Physics State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, P. R. China
| | - Songting Tan
- Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105, P. R. China
| | - Feng Gao
- Department of Physics, Chemistry, and Biology, Linköping University, Linköping 58183, Sweden
| | - Xiaowei Zhan
- Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing 100871, P. R. China
| | - Yanming Sun
- School of Chemistry, Beihang University, Beijing 100191, P. R. China
| |
Collapse
|
8
|
Perdigón-Toro L, Zhang H, Markina A, Yuan J, Hosseini SM, Wolff CM, Zuo G, Stolterfoht M, Zou Y, Gao F, Andrienko D, Shoaee S, Neher D. Barrierless Free Charge Generation in the High-Performance PM6:Y6 Bulk Heterojunction Non-Fullerene Solar Cell. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e1906763. [PMID: 31975446 DOI: 10.1002/adma.201906763] [Citation(s) in RCA: 97] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 12/19/2019] [Indexed: 05/22/2023]
Abstract
Organic solar cells are currently experiencing a second golden age thanks to the development of novel non-fullerene acceptors (NFAs). Surprisingly, some of these blends exhibit high efficiencies despite a low energy offset at the heterojunction. Herein, free charge generation in the high-performance blend of the donor polymer PM6 with the NFA Y6 is thoroughly investigated as a function of internal field, temperature and excitation energy. Results show that photocurrent generation is essentially barrierless with near-unity efficiency, regardless of excitation energy. Efficient charge separation is maintained over a wide temperature range, down to 100 K, despite the small driving force for charge generation. Studies on a blend with a low concentration of the NFA, measurements of the energetic disorder, and theoretical modeling suggest that CT state dissociation is assisted by the electrostatic interfacial field which for Y6 is large enough to compensate the Coulomb dissociation barrier.
Collapse
Affiliation(s)
- Lorena Perdigón-Toro
- Soft Matter Physics, Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam-Golm, Germany
- Disordered Semiconductor Optoelectronics, Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam-Golm, Germany
| | - Huotian Zhang
- Department of Physics, Chemistry and Biology (IFM), Linköping University, 581 83, Linköping, Sweden
| | - Anastasia Markina
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Jun Yuan
- College of Chemistry and Chemical Engineering, Central South University, Changsha, 410083, P. R. China
| | - Seyed Mehrdad Hosseini
- Disordered Semiconductor Optoelectronics, Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam-Golm, Germany
| | - Christian M Wolff
- Soft Matter Physics, Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam-Golm, Germany
| | - Guangzheng Zuo
- Soft Matter Physics, Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam-Golm, Germany
| | - Martin Stolterfoht
- Soft Matter Physics, Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam-Golm, Germany
| | - Yingping Zou
- College of Chemistry and Chemical Engineering, Central South University, Changsha, 410083, P. R. China
| | - Feng Gao
- Department of Physics, Chemistry and Biology (IFM), Linköping University, 581 83, Linköping, Sweden
| | - Denis Andrienko
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Safa Shoaee
- Disordered Semiconductor Optoelectronics, Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam-Golm, Germany
| | - Dieter Neher
- Soft Matter Physics, Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam-Golm, Germany
| |
Collapse
|
9
|
Firdaus Y, Le Corre VM, Khan JI, Kan Z, Laquai F, Beaujuge PM, Anthopoulos TD. Key Parameters Requirements for Non-Fullerene-Based Organic Solar Cells with Power Conversion Efficiency >20. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2019; 6:1802028. [PMID: 31065524 PMCID: PMC6498106 DOI: 10.1002/advs.201802028] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 02/05/2019] [Indexed: 05/23/2023]
Abstract
The reported power conversion efficiencies (PCEs) of nonfullerene acceptor (NFA) based organic photovoltaics (OPVs) now exceed 14% and 17% for single-junction and two-terminal tandem cells, respectively. However, increasing the PCE further requires an improved understanding of the factors limiting the device efficiency. Here, the efficiency limits of single-junction and two-terminal tandem NFA-based OPV cells are examined with the aid of a numerical device simulator that takes into account the optical properties of the active material(s), charge recombination effects, and the hole and electron mobilities in the active layer of the device. The simulations reveal that single-junction NFA OPVs can potentially reach PCE values in excess of 18% with mobility values readily achievable in existing material systems. Furthermore, it is found that balanced electron and hole mobilities of >10-3 cm2 V-1 s-1 in combination with low nongeminate recombination rate constants of 10-12 cm3 s-1 could lead to PCE values in excess of 20% and 25% for single-junction and two-terminal tandem OPV cells, respectively. This analysis provides the first tangible description of the practical performance targets and useful design rules for single-junction and tandem OPVs based on NFA materials, emphasizing the need for developing new material systems that combine these desired characteristics.
Collapse
Affiliation(s)
- Yuliar Firdaus
- King Abdullah University of Science and Technology (KAUST)KAUST Solar Center (KSC)Division of Physical Sciences and EngineeringThuwal23955–6900Saudi Arabia
| | - Vincent M. Le Corre
- University of GroningenZernike Institute for Advanced MaterialsNijenborgh 49747AGGroningenThe Netherlands
| | - Jafar I. Khan
- King Abdullah University of Science and Technology (KAUST)KAUST Solar Center (KSC)Division of Physical Sciences and EngineeringThuwal23955–6900Saudi Arabia
| | - Zhipeng Kan
- King Abdullah University of Science and Technology (KAUST)KAUST Solar Center (KSC)Division of Physical Sciences and EngineeringThuwal23955–6900Saudi Arabia
| | - Frédéric Laquai
- King Abdullah University of Science and Technology (KAUST)KAUST Solar Center (KSC)Division of Physical Sciences and EngineeringThuwal23955–6900Saudi Arabia
| | - Pierre M. Beaujuge
- King Abdullah University of Science and Technology (KAUST)KAUST Solar Center (KSC)Division of Physical Sciences and EngineeringThuwal23955–6900Saudi Arabia
| | - Thomas D. Anthopoulos
- King Abdullah University of Science and Technology (KAUST)KAUST Solar Center (KSC)Division of Physical Sciences and EngineeringThuwal23955–6900Saudi Arabia
- Department of PhysicsImperial College LondonSouth KensingtonLondonSW7 2AZUK
| |
Collapse
|
10
|
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.
Collapse
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
| |
Collapse
|
11
|
Roland S, Kniepert J, Love JA, Negi V, Liu F, Bobbert P, Melianas A, Kemerink M, Hofacker A, Neher D. Equilibrated Charge Carrier Populations Govern Steady-State Nongeminate Recombination in Disordered Organic Solar Cells. J Phys Chem Lett 2019; 10:1374-1381. [PMID: 30829040 DOI: 10.1021/acs.jpclett.9b00516] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We employed bias-assisted charge extraction techniques to investigate the transient and steady-state recombination of photogenerated charge carriers in complete devices of a disordered polymer-fullerene blend. Charge recombination is shown to be dispersive, with a significant slowdown of the recombination rate over time, consistent with the results from kinetic Monte Carlo simulations. Surprisingly, our experiments reveal little to no contributions from early time recombination of nonequilibrated charge carriers to the steady-state recombination properties. We conclude that energetic relaxation of photogenerated carriers outpaces any significant nongeminate recombination under application-relevant illumination conditions. With equilibrated charges dominating the steady-state recombination, quasi-equilibrium concepts appear suited for describing the open-circuit voltage of organic solar cells despite pronounced energetic disorder.
Collapse
Affiliation(s)
- Steffen Roland
- Department of Physics and Astronomy , Universität Potsdam , 14476 Potsdam , Germany
| | - Juliane Kniepert
- Department of Physics and Astronomy , Universität Potsdam , 14476 Potsdam , Germany
| | - John A Love
- Department of Physics and Astronomy , Universität Potsdam , 14476 Potsdam , Germany
| | - Vikas Negi
- Molecular Materials and Nanosystems, Department of Applied Physics , Eindhoven University of Technology , P.O. Box 513, 5600 MB Eindhoven , The Netherlands
| | - Feilong Liu
- Molecular Materials and Nanosystems, Department of Applied Physics , Eindhoven University of Technology , P.O. Box 513, 5600 MB Eindhoven , The Netherlands
| | - Peter Bobbert
- Molecular Materials and Nanosystems, Department of Applied Physics , Eindhoven University of Technology , P.O. Box 513, 5600 MB Eindhoven , The Netherlands
| | - Armantas Melianas
- 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
| | - Andreas Hofacker
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics , Technische Universität Dresden , 01187 Dresden , Germany
| | - Dieter Neher
- Department of Physics and Astronomy , Universität Potsdam , 14476 Potsdam , Germany
| |
Collapse
|
12
|
Collado-Fregoso E, Pugliese SN, Wojcik M, Benduhn J, Bar-Or E, Perdigón Toro L, Hörmann U, Spoltore D, Vandewal K, Hodgkiss JM, Neher D. Energy-Gap Law for Photocurrent Generation in Fullerene-Based Organic Solar Cells: The Case of Low-Donor-Content Blends. J Am Chem Soc 2019; 141:2329-2341. [PMID: 30620190 DOI: 10.1021/jacs.8b09820] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The involvement of charge-transfer (CT) states in the photogeneration and recombination of charge carriers has been an important focus of study within the organic photovoltaic community. In this work, we investigate the molecular factors determining the mechanism of photocurrent generation in low-donor-content organic solar cells, where the active layer is composed of vacuum-deposited C60 and small amounts of organic donor molecules. We find a pronounced decline of all photovoltaic parameters with decreasing CT state energy. Using a combination of steady-state photocurrent measurements and time-delayed collection field experiments, we demonstrate that the power conversion efficiency, and more specifically, the fill factor of these devices, is mainly determined by the bias dependence of photocurrent generation. By combining these findings with the results from ultrafast transient absorption spectroscopy, we show that blends with small CT energies perform poorly because of an increased nonradiative CT state decay rate and that this decay obeys an energy-gap law. Our work challenges the common view that a large energy offset at the heterojunction and/or the presence of fullerene clusters guarantee efficient CT dissociation and rather indicates that charge generation benefits from high CT state energies through a slower decay to the ground state.
Collapse
Affiliation(s)
- Elisa Collado-Fregoso
- Department of Physics and Astronomy , University of Potsdam , Karl-Liebknecht-Straße 24-25 , 14476 Potsdam-Golm , Germany
| | - Silvina N Pugliese
- School of Chemical and Physical Sciences , Victoria University of Wellington , Wellington 6040 , New Zealand.,The MacDiarmid Institute for Advanced Materials and Nanotechnology , Wellington 6040 , New Zealand
| | - Mariusz Wojcik
- Institute of Applied Radiation Chemistry , Lodz University of Technology , Wroblewskiego 15 , 93590 Lodz , Poland
| | - Johannes Benduhn
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics , Technische Universität Dresden , Nöthnitzer Straße 61 , 01187 Dresden , Germany
| | - Eyal Bar-Or
- Department of Physics and Astronomy , University of Potsdam , Karl-Liebknecht-Straße 24-25 , 14476 Potsdam-Golm , Germany
| | - Lorena Perdigón Toro
- Department of Physics and Astronomy , University of Potsdam , Karl-Liebknecht-Straße 24-25 , 14476 Potsdam-Golm , Germany
| | - Ulrich Hörmann
- Department of Physics and Astronomy , University of Potsdam , Karl-Liebknecht-Straße 24-25 , 14476 Potsdam-Golm , Germany
| | - Donato Spoltore
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics , Technische Universität Dresden , Nöthnitzer Straße 61 , 01187 Dresden , Germany
| | - Koen Vandewal
- Institute for Materials Research (IMO-IMOMEC) , Hasselt University , Wetenschapspark 1 , 3590 Diepenbeek , Belgium
| | - Justin M Hodgkiss
- School of Chemical and Physical Sciences , Victoria University of Wellington , Wellington 6040 , New Zealand.,The MacDiarmid Institute for Advanced Materials and Nanotechnology , Wellington 6040 , New Zealand
| | - Dieter Neher
- Department of Physics and Astronomy , University of Potsdam , Karl-Liebknecht-Straße 24-25 , 14476 Potsdam-Golm , Germany
| |
Collapse
|
13
|
Kurpiers J, Ferron T, Roland S, Jakoby M, Thiede T, Jaiser F, Albrecht S, Janietz S, Collins BA, Howard IA, Neher D. Probing the pathways of free charge generation in organic bulk heterojunction solar cells. Nat Commun 2018; 9:2038. [PMID: 29795114 PMCID: PMC5966440 DOI: 10.1038/s41467-018-04386-3] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 04/24/2018] [Indexed: 11/30/2022] Open
Abstract
The fact that organic solar cells perform efficiently despite the low dielectric constant of most photoactive blends initiated a long-standing debate regarding the dominant pathways of free charge formation. Here, we address this issue through the accurate measurement of the activation energy for free charge photogeneration over a wide range of photon energy, using the method of time-delayed collection field. For our prototypical low bandgap polymer:fullerene blends, we find that neither the temperature nor the field dependence of free charge generation depend on the excitation energy, ruling out an appreciable contribution to free charge generation though hot carrier pathways. On the other hand, activation energies are on the order of the room temperature thermal energy for all studied blends. We conclude that charge generation in such devices proceeds through thermalized charge transfer states, and that thermal energy is sufficient to separate most of these states into free charges. Contradictory models are being debated on the dominant pathways of charge generation in organic solar cells. Here Kurpiers et al. determine the activation energy for this fundamental process and reveal that the main channel is via thermalized charge transfer states instead of hot exciton dissociation.
Collapse
Affiliation(s)
- Jona Kurpiers
- Institute of Physics and Astronomy, Soft Matter Physics, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam-Golm, Germany
| | - Thomas Ferron
- Department of Physics and Astronomy, Washington State University, 100 Dairy Road, Pullman, WA, 99164, USA
| | - Steffen Roland
- Institute of Physics and Astronomy, Soft Matter Physics, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam-Golm, Germany
| | - Marius Jakoby
- Karlsruhe Institute of Technology (KIT), Institute of Microstructure Technology (IMT), Hermann-von-Helmholtz Platz-1, 76344, Eggenstein-Leopoldshafen, Germany
| | - Tobias Thiede
- Institute of Physics and Astronomy, Soft Matter Physics, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam-Golm, Germany
| | - Frank Jaiser
- Institute of Physics and Astronomy, Soft Matter Physics, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam-Golm, Germany
| | - Steve Albrecht
- Helmholtz-Zentrum Berlin für Materialien und Energie, Nachwuchsgruppe Perowskit Tandemsolarzellen, Kekuléstraße 5, 12489, Berlin, Germany
| | - Silvia Janietz
- Fraunhofer IAP, Polymere und Elektronik, Geiselbergstraße 69, 14476, Potsdam-Golm, Germany
| | - Brian A Collins
- Department of Physics and Astronomy, Washington State University, 100 Dairy Road, Pullman, WA, 99164, USA
| | - Ian A Howard
- Karlsruhe Institute of Technology (KIT), Institute of Microstructure Technology (IMT), Hermann-von-Helmholtz Platz-1, 76344, Eggenstein-Leopoldshafen, Germany
| | - Dieter Neher
- Institute of Physics and Astronomy, Soft Matter Physics, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam-Golm, Germany.
| |
Collapse
|
14
|
Love JA, Feuerstein M, Wolff CM, Facchetti A, Neher D. Lead Halide Perovskites as Charge Generation Layers for Electron Mobility Measurement in Organic Semiconductors. ACS APPLIED MATERIALS & INTERFACES 2017; 9:42011-42019. [PMID: 29083145 DOI: 10.1021/acsami.7b10361] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Hybrid lead halide perovskites are introduced as charge generation layers (CGLs) for the accurate determination of electron mobilities in thin organic semiconductors. Such hybrid perovskites have become a widely studied photovoltaic material in their own right, for their high efficiencies, ease of processing from solution, strong absorption, and efficient photogeneration of charge. Time-of-flight (ToF) measurements on bilayer samples consisting of the perovskite CGL and an organic semiconductor layer of different thickness are shown to be determined by the carrier motion through the organic material, consistent with the much higher charge carrier mobility in the perovskite. Together with the efficient photon-to-electron conversion in the perovskite, this high mobility imbalance enables electron-only mobility measurement on relatively thin application-relevant organic films, which would not be possible with traditional ToF measurements. This architecture enables electron-selective mobility measurements in single components as well as bulk-heterojunction films as demonstrated in the prototypical polymer/fullerene blends. To further demonstrate the potential of this approach, electron mobilities were measured as a function of electric field and temperature in an only 127 nm thick layer of a prototypical electron-transporting perylene diimide-based polymer, and found to be consistent with an exponential trap distribution of ca. 60 meV. Our study furthermore highlights the importance of high mobility charge transporting layers when designing perovskite solar cells.
Collapse
Affiliation(s)
- John A Love
- Institute for Physics and Astronomy, University of Potsdam , Karl-Liebknecht-Straße 24-25, Potsdam-Golm 14476, Germany
| | - Markus Feuerstein
- Institute for Physics and Astronomy, University of Potsdam , Karl-Liebknecht-Straße 24-25, Potsdam-Golm 14476, Germany
| | - Christian M Wolff
- Institute for Physics and Astronomy, University of Potsdam , Karl-Liebknecht-Straße 24-25, Potsdam-Golm 14476, Germany
| | - Antonio Facchetti
- Department of Chemistry and The Materials Research Center, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Dieter Neher
- Institute for Physics and Astronomy, University of Potsdam , Karl-Liebknecht-Straße 24-25, Potsdam-Golm 14476, Germany
| |
Collapse
|
15
|
Collado-Fregoso E, Hood SN, Shoaee S, Schroeder BC, McCulloch I, Kassal I, Neher D, Durrant JR. Intercalated vs Nonintercalated Morphologies in Donor-Acceptor Bulk Heterojunction Solar Cells: PBTTT:Fullerene Charge Generation and Recombination Revisited. J Phys Chem Lett 2017; 8:4061-4068. [PMID: 28777583 DOI: 10.1021/acs.jpclett.7b01571] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In this Letter, we study the role of the donor:acceptor interface nanostructure upon charge separation and recombination in organic photovoltaic devices and blend films, using mixtures of PBTTT and two different fullerene derivatives (PC70BM and ICTA) as models for intercalated and nonintercalated morphologies, respectively. Thermodynamic simulations show that while the completely intercalated system exhibits a large free-energy barrier for charge separation, this barrier is significantly lower in the nonintercalated system and almost vanishes when energetic disorder is included in the model. Despite these differences, both femtosecond-resolved transient absorption spectroscopy (TAS) and time-delayed collection field (TDCF) exhibit extensive first-order losses in both systems, suggesting that geminate pairs are the primary product of photoexcitation. In contrast, the system that comprises a combination of fully intercalated polymer:fullerene areas and fullerene-aggregated domains (1:4 PBTTT:PC70BM) is the only one that shows slow, second-order recombination of free charges, resulting in devices with an overall higher short-circuit current and fill factor. This study therefore provides a novel consideration of the role of the interfacial nanostructure and the nature of bound charges and their impact upon charge generation and recombination.
Collapse
Affiliation(s)
- Elisa Collado-Fregoso
- Department of Physics and Astronomy, University of Potsdam , Karl-Liebknecht-Straße 24-25, 14476 Potsdam-Golm, Germany
- Centre for Plastic Electronics, Department of Chemistry, Imperial College London , Exhibition Road, London SW7 2AZ, United Kingdom
| | - Samantha N Hood
- Centre for Engineered Quantum Systems, School of Mathematics and Physics, The University of Queensland , Brisbane, Queensland 4072, Australia
| | - Safa Shoaee
- Department of Physics and Astronomy, University of Potsdam , Karl-Liebknecht-Straße 24-25, 14476 Potsdam-Golm, Germany
| | - Bob C Schroeder
- Materials Research Institute and School of Biological and Chemical Sciences, Queen Mary University of London , Mile End Road, London E1 4NS, United Kingdom
- Centre for Plastic Electronics, Department of Chemistry, Imperial College London , Exhibition Road, London SW7 2AZ, United Kingdom
| | - Iain McCulloch
- Centre for Plastic Electronics, Department of Chemistry, Imperial College London , Exhibition Road, London SW7 2AZ, United Kingdom
- KSC, King Abdullah University of Science and Technology , Thuwal 23955-6900, Saudi Arabia
| | - Ivan Kassal
- Centre for Engineered Quantum Systems, School of Mathematics and Physics, The University of Queensland , Brisbane, Queensland 4072, Australia
- Centre for Engineered Quantum Systems, Australian Institute for Nanoscale Science and Technology, and School of Chemistry, The University of Sydney , Sydney, New South Wales 2006, Australia
| | - Dieter Neher
- Department of Physics and Astronomy, University of Potsdam , Karl-Liebknecht-Straße 24-25, 14476 Potsdam-Golm, Germany
| | - James R Durrant
- Centre for Plastic Electronics, Department of Chemistry, Imperial College London , Exhibition Road, London SW7 2AZ, United Kingdom
- SPECIFIC IKC, College of Engineering, Swansea University , Swansea SA12 7AX, United Kingdom
| |
Collapse
|