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He B, Wang C, Li J, Su Z, Xing G, Gao X, Chen S. In Situ and Operando Characterization Techniques in Stability Study of Perovskite-Based Devices. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:1983. [PMID: 37446498 DOI: 10.3390/nano13131983] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Revised: 06/13/2023] [Accepted: 06/15/2023] [Indexed: 07/15/2023]
Abstract
Metal halide perovskite materials have demonstrated significant potential in various optoelectronic applications, such as photovoltaics, light emitting diodes, photodetectors, and lasers. However, the stability issues of perovskite materials continue to impede their widespread use. Many studies have attempted to understand the complex degradation mechanism and dynamics of these materials. Among them, in situ and/or operando approaches have provided remarkable insights into the degradation process by enabling precise control of degradation parameters and real-time monitoring. In this review, we focus on these studies utilizing in situ and operando approaches and demonstrate how these techniques have contributed to reveal degradation details, including structural, compositional, morphological, and other changes. We explore why these two approaches are necessary in the study of perovskite degradation and how they can be achieved by upgrading the corresponding ex situ techniques. With recent stability improvements of halide perovskite using various methods (compositional engineering, surface engineering, and structural engineering), the degradation of halide perovskite materials is greatly retarded. However, these improvements may turn into new challenges during the investigation into the retarded degradation process. Therefore, we also highlight the importance of enhancing the sensitivity and probing range of current in situ and operando approaches to address this issue. Finally, we identify the challenges and future directions of in situ and operando approaches in the stability research of halide perovskites. We believe that the advancement of in situ and operando techniques will be crucial in supporting the journey toward enhanced perovskite stability.
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Affiliation(s)
- Bingchen He
- Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Avenida da Universidade, Taipa, Macau 999078, China
| | - Chenyue Wang
- Shanghai Synchrotron Radiation Facility (SSRF), Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, China
| | - Jielei Li
- Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Avenida da Universidade, Taipa, Macau 999078, China
| | - Zhenhuang Su
- Shanghai Synchrotron Radiation Facility (SSRF), Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, China
| | - Guichuan Xing
- Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Avenida da Universidade, Taipa, Macau 999078, China
| | - Xingyu Gao
- Shanghai Synchrotron Radiation Facility (SSRF), Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, China
| | - Shi Chen
- Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Avenida da Universidade, Taipa, Macau 999078, China
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2
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Nguyen TMH, Shin SG, Choi HW, Bark CW. Recent advances in self-powered and flexible UVC photodetectors. EXPLORATION (BEIJING, CHINA) 2022; 2:20210078. [PMID: 37325501 PMCID: PMC10190973 DOI: 10.1002/exp.20210078] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Accepted: 04/14/2022] [Indexed: 06/17/2023]
Abstract
Ultraviolet-C (UVC) radiation is employed in various applications, including irreplaceable applications in military and civil fields, such as missile guidance, flame detection, partial discharge detection, disinfection, and wireless communication. Although most modern electronics are based on Si, UVC detection technology remains a unique exception because the short wavelength of UV radiation makes efficient detection with Si difficult. In this review, recent challenges in obtaining ideal UVC photodetectors with various materials and various forms are introduced. An ideal photodetector must satisfy the following requirements: high sensitivity, fast response speed, high on/off photocurrent ratio, good regional selectivity, outstanding reproducibility, and superior thermal and photo stabilities. UVC detection is still in its infancy compared to the detection of UVA as well as other photon spectra, and recent research has focused on different key components, including the configuration, material, and substrate, to acquire battery-free, super-sensitive, ultra-stable, ultra-small, and portable UVC photodetectors. We introduce and discuss the strategies for fabricating self-powered UVC photodetectors on flexible substrates in terms of the structure, material, and direction of incoming radiation. We also explain the physical mechanisms of self-powered devices with various architectures. Finally, we present a brief outlook that discusses the challenges and future strategies for deep-UVC photodetectors.
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Affiliation(s)
- Thi My Huyen Nguyen
- Department of Electrical Engineering Gachon University Seongnam Gyeonggi Republic of Korea
| | - Seong Gwan Shin
- Department of Electrical Engineering Gachon University Seongnam Gyeonggi Republic of Korea
| | - Hyung Wook Choi
- Department of Electrical Engineering Gachon University Seongnam Gyeonggi Republic of Korea
| | - Chung Wung Bark
- Department of Electrical Engineering Gachon University Seongnam Gyeonggi Republic of Korea
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3
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Bhatia H, Ghosh B, Debroye E. Colloidal FAPbBr 3 perovskite nanocrystals for light emission: what's going on? JOURNAL OF MATERIALS CHEMISTRY. C 2022; 10:13437-13461. [PMID: 36324302 PMCID: PMC9521414 DOI: 10.1039/d2tc01373h] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 05/06/2022] [Indexed: 06/16/2023]
Abstract
Semiconducting nanomaterials have been widely explored in diverse optoelectronic applications. Colloidal lead halide perovskite nanocrystals (NCs) have recently been an excellent addition to the field of nanomaterials, promising an enticing building block in the field of light emission. In addition to the notable optoelectronic properties of perovskites, the colloidal NCs exhibit unique size-dependent optical properties due to the quantum size effect, which makes them highly attractive for light-emitting diodes (LEDs). In the past few years, perovskite-based LEDs (PeLEDs) have demonstrated a meteoritic rise in their external quantum efficiency (EQE) values, reaching over 20% so far. Among various halide perovskite compositions, FAPbBr3 and its variants remain one of the most interesting and sought-after compounds for green light emission. This review focuses on recent progress in the design and synthesis protocols of colloidal FAPbBr3 NCs and the emerging concepts in tailoring their surface chemistry. The structural and physicochemical features of lead halide perovskites along with a comprehensive discussion on their defect-tolerant properties are briefly outlined. Later, the prevalent synthesis, ligand, and compositional engineering strategies to boost the stability and photoluminescence quantum yield (PLQY) of FAPbBr3 NCs are extensively discussed. Finally, the fundamental concepts and recent progress on FAPbBr3-based LEDs, followed by a discussion of the challenges and prospects that are on the table for this enticing class of perovskites, are reviewed.
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Affiliation(s)
- Harshita Bhatia
- Department of Chemistry, KU Leuven Celestijnenlaan 200F B-3001 Leuven Belgium
| | - Biplab Ghosh
- cMACS, Department of Microbial and Molecular Systems, KU Leuven Celestijnenlaan 200F B-3001 Leuven Belgium
| | - Elke Debroye
- Department of Chemistry, KU Leuven Celestijnenlaan 200F B-3001 Leuven Belgium
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4
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Sun X, Zhang Y, Ge W. Photo-induced macro/mesoscopic scale ion displacement in mixed-halide perovskites: ring structures and ionic plasma oscillations. LIGHT, SCIENCE & APPLICATIONS 2022; 11:262. [PMID: 36068199 PMCID: PMC9448785 DOI: 10.1038/s41377-022-00957-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 08/14/2022] [Accepted: 08/16/2022] [Indexed: 05/26/2023]
Abstract
Contrary to the common belief that the light-induced halide ion segregation in a mixed halide alloy occurs within the illuminated area, we find that the Br ions released by light are expelled from the illuminated area, which generates a macro/mesoscopic size anion ring surrounding the illuminated area, exhibiting a photoluminescence ring. This intriguing phenomenon can be explained as resulting from two counter-balancing effects: the outward diffusion of the light-induced free Br ions and the Coulombic force between the anion deficit and surplus region. Right after removing the illumination, the macro/mesoscopic scale ion displacement results in a built-in voltage of about 0.4 V between the ring and the center. Then, the displaced anions return to the illuminated area, and the restoring force leads to a damped ultra-low-frequency oscillatory ion motion, with a period of about 20-30 h and lasting over 100 h. This finding may be the first observation of an ionic plasma oscillation in solids. Our understanding and controlling the "ion segregation" demonstrate that it is possible to turn this commonly viewed "adverse phenomenon" into novel electronic applications, such as ionic patterning, self-destructive memory, and energy storage.
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Affiliation(s)
- Xiaoxiao Sun
- Laboratory for Thin Films and Photovoltaics, Empa-Swiss Federal Laboratories for Materials Science and Technology, 8600, Duebendorf, Switzerland.
- Department of Information Technology and Electrical Engineering, ETH Zurich, 8093, Zurich, Switzerland.
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, 01328, Germany.
| | - Yong Zhang
- Department of Electrical and Computer Engineering, The University of North Carolina at Charlotte, Charlotte, NC, 28223, USA.
| | - Weikun Ge
- Department of Physics, Tsinghua University, Beijing, 10084, People's Republic of China
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5
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Liu H, Li N, Chen Z, Tao S, Li C, Jiang L, Niu X, Chen Q, Wang F, Zhang Y, Huang Z, Song T, Zhou H. Reversible Phase Transition for Durable Formamidinium-Dominated Perovskite Photovoltaics. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2204458. [PMID: 35950226 DOI: 10.1002/adma.202204458] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 07/28/2022] [Indexed: 06/15/2023]
Abstract
Phase instability is one of the major obstacles to the wide application of formamidinium (FA)-dominated perovskite solar cells (PSCs). An in-depth investigation on relevant phase transitions is urgently needed to explore more effective phase-stabilization strategies. Herein, the reversible phase-transition process of FA1- x Csx PbI3 perovskite between photoactive phase (α phase) and non-photoactive phase (δ phase) under humidity, as well as the reversible healing of degraded devices, is monitored. Moreover, through in situ atomic force microscopy, the kinetic transition between α and δ phase is revealed to be the "nucleation-growth transition" process. Density functional theory calculation implies an enthalpy-driven α-to-δ degradation process during humidity aging and an entropy-driven δ-to-α healing process at high temperatures. The α phase of FA1- x Csx PbI3 can be stabilized at elevated temperature under high humidity due to the increased nucleation barrier, and the resulting non-encapsulated PSCs retain >90% of their initial efficiency after >1000 h at 60 °C and 60% relative humidity. This finding provides a deepened understanding on the phase-transition process of FA1- x Csx PbI3 from both thermodynamics and kinetics points of view, which also presents an effective means to stabilize the α phase of FA-dominated perovskites and devices for practical applications.
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Affiliation(s)
- Huifen Liu
- Beijing Key Laboratory for Theory and Technology of Advanced Battery Materials, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, School of Materials Science and Engineering, Peking University, Beijing, 100871, P. R. China
| | - Nengxu Li
- Beijing Key Laboratory for Theory and Technology of Advanced Battery Materials, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, School of Materials Science and Engineering, Peking University, Beijing, 100871, P. R. China
| | - Zehua Chen
- Materials Simulation and Modelling, Department of Applied Physics, Eindhoven University of Technology, Eindhoven, 5600 MB, The Netherlands
- Center for Computational Energy Research, Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, Eindhoven, 5600 MB, The Netherlands
| | - Shuxia Tao
- Materials Simulation and Modelling, Department of Applied Physics, Eindhoven University of Technology, Eindhoven, 5600 MB, The Netherlands
- Center for Computational Energy Research, Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, Eindhoven, 5600 MB, The Netherlands
| | - Chunlei Li
- Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
| | - Lang Jiang
- Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
| | - Xiuxiu Niu
- School of Materials Science and Engineering, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Qi Chen
- School of Materials Science and Engineering, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Feng Wang
- Beijing Key Laboratory for Theory and Technology of Advanced Battery Materials, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, School of Materials Science and Engineering, Peking University, Beijing, 100871, P. R. China
| | - Yu Zhang
- Beijing Key Laboratory for Theory and Technology of Advanced Battery Materials, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, School of Materials Science and Engineering, Peking University, Beijing, 100871, P. R. China
| | - Zijian Huang
- Beijing Key Laboratory for Theory and Technology of Advanced Battery Materials, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, School of Materials Science and Engineering, Peking University, Beijing, 100871, P. R. China
| | - Tinglu Song
- School of Materials Science and Engineering, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Huanping Zhou
- Beijing Key Laboratory for Theory and Technology of Advanced Battery Materials, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, School of Materials Science and Engineering, Peking University, Beijing, 100871, P. R. China
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6
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Feng S, Qin Q, Han X, Zhang C, Wang X, Yu T, Xiao M. Universal Existence of Localized Single-Photon Emitters in the Perovskite Film of All-Inorganic CsPbBr 3 Microcrystals. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2106278. [PMID: 34687093 DOI: 10.1002/adma.202106278] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 09/17/2021] [Indexed: 06/13/2023]
Abstract
All-inorganic halide perovskites have drawn a lot of research attention very recently owing to their potential solution to the instability issue currently faced by the organic-inorganic counterparts. Meanwhile, the halide perovskites in a solid film are manifested as microscale morphologies whose functionalities are unavoidably affected by the interior or exterior presence of various nanoscale entities. Here all-inorganic solid films are fabricated with varying densities of single CsPbBr3 microcrystals, showing that very sharp photoluminescence peaks can be universally observed at 4 K with the linewidths being as narrow as hundreds of μeV. The single-photon emission nature is confirmed for such a photoluminescence peak, whose intensity is completely quenched above ≈30 K to suggest its possible origin from a low potential-energy region of the single microcrystal. The discovery of such a novel emitting species in halide perovskites, with the enriched structure-property relationship, will surely impart significant influences on the advancement of relevant optoelectronic devices and quantum-light sources.
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Affiliation(s)
- Shengnan Feng
- School of Physics, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Qilin Qin
- School of Physics, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Xiaopeng Han
- School of Physics, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Chunfeng Zhang
- School of Physics, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Xiaoyong Wang
- School of Physics, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Tao Yu
- School of Physics, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Min Xiao
- School of Physics, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
- Department of Physics, University of Arkansas, Fayetteville, AR, 72701, USA
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7
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Huang T, Tan S, Nuryyeva S, Yavuz I, Babbe F, Zhao Y, Abdelsamie M, Weber MH, Wang R, Houk KN, Sutter-Fella CM, Yang Y. Performance-limiting formation dynamics in mixed-halide perovskites. SCIENCE ADVANCES 2021; 7:eabj1799. [PMID: 34757790 PMCID: PMC8580316 DOI: 10.1126/sciadv.abj1799] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Wide-bandgap (WBG) mixed-halide perovskites as the front cell absorber are accomplishing perovskite-based tandem solar cells with over 29% power conversion efficiency. However, their large voltage deficits limit their ultimate performance. Only a handful of studies probe the fundamental mechanisms underlying the voltage deficits, which remain an unsolved challenge in the field. In this study, we investigate the formation dynamics and defect physics of WBG mixed-halide perovskites in contrast with their corresponding triiodide-based perovskites. Our results show that the inclusion of bromide introduced a halide homogenization process that occurs during the perovskite growth stage from an initial bromide-rich phase toward the final target stoichiometry. We further elucidated a physical model that correlates the role of bromide with the formation dynamics, defect physics, and eventual optoelectronic properties of the film. This work provides a fundamental and unique perspective toward understanding the performance-limiting factors affecting WBG mixed-halide perovskites.
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Affiliation(s)
- Tianyi Huang
- Department of Materials Science and Engineering and California NanoSystems Institute, University of California Los Angeles, Los Angeles, CA 90095, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Shaun Tan
- Department of Materials Science and Engineering and California NanoSystems Institute, University of California Los Angeles, Los Angeles, CA 90095, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Selbi Nuryyeva
- Department of Chemistry, University of California, Los Angeles, CA 90095, USA
| | - Ilhan Yavuz
- Department of Physics, Marmara University, 34722 Ziverbey, Istanbul, Turkey
- Corresponding author. (Y.Y.); (C.M.S.-F.); (I.Y.)
| | - Finn Babbe
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Yepin Zhao
- Department of Materials Science and Engineering and California NanoSystems Institute, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Maged Abdelsamie
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Marc H. Weber
- Center for Materials Research, Washington State University, Pullman, WA 99164, USA
| | - Rui Wang
- Department of Materials Science and Engineering and California NanoSystems Institute, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Kendall N. Houk
- Department of Chemistry, University of California, Los Angeles, CA 90095, USA
| | - Carolin M. Sutter-Fella
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Corresponding author. (Y.Y.); (C.M.S.-F.); (I.Y.)
| | - Yang Yang
- Department of Materials Science and Engineering and California NanoSystems Institute, University of California Los Angeles, Los Angeles, CA 90095, USA
- Corresponding author. (Y.Y.); (C.M.S.-F.); (I.Y.)
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8
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DuBose JT, Mathew PS, Cho J, Kuno M, Kamat PV. Modulation of Photoinduced Iodine Expulsion in Mixed Halide Perovskites with Electrochemical Bias. J Phys Chem Lett 2021; 12:2615-2621. [PMID: 33689371 DOI: 10.1021/acs.jpclett.1c00367] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Hole trapping at iodine (I) sites in MAPbBr1.5I1.5 mixed halide perovskites (MHP) is responsible for iodine migration and its eventual expulsion into solution. We have now modulated the photoinduced iodine expulsion in MHP through an externally applied electrochemical bias. At positive potentials, electron extraction at TiO2/MHP interfaces becomes efficient, leading to hole buildup within MHP films. This improved charge separation, in turn, favors iodine migration as evident from the increased apparent rate constant of iodine expulsion (kexpulsion = 0.0030 s-1). Conversely, at negative potentials (-0.3 V vs Ag/AgCl) electron-hole recombination is facilitated within MHP, slowing down iodine expulsion by an order of magnitude (kexpulsion = 0.00018 s-1). The tuning of the EFermi level through external bias modulates electron extraction at the TiO2/MHP interface and indirectly controls the buildup of holes, ultimately inducing iodine migration/expulsion. Suppressing iodine migration in perovskite solar cells is important for attaining greater stability since they operate under internal electrical bias.
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9
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Knight AJ, Borchert J, Oliver RDJ, Patel JB, Radaelli PG, Snaith HJ, Johnston MB, Herz LM. Halide Segregation in Mixed-Halide Perovskites: Influence of A-Site Cations. ACS ENERGY LETTERS 2021; 6:799-808. [PMID: 33614967 PMCID: PMC7888268 DOI: 10.1021/acsenergylett.0c02475] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 01/27/2021] [Indexed: 05/09/2023]
Abstract
Mixed-halide perovskites offer bandgap tunability essential for multijunction solar cells; however, a detrimental halide segregation under light is often observed. Here we combine simultaneous in situ photoluminescence and X-ray diffraction measurements to demonstrate clear differences in compositional and optoelectronic changes associated with halide segregation in MAPb(Br0.5I0.5)3 and FA0.83Cs0.17Pb(Br0.4I0.6)3 films. We report evidence for low-barrier ionic pathways in MAPb(Br0.5I0.5)3, which allow for the rearrangement of halide ions in localized volumes of perovskite without significant compositional changes to the bulk material. In contrast, FA0.83Cs0.17Pb(Br0.4I0.6)3 lacks such low-barrier ionic pathways and is, consequently, more stable against halide segregation. However, under prolonged illumination, it exhibits a considerable ionic rearrangement throughout the bulk material, which may be triggered by an initial demixing of A-site cations, altering the composition of the bulk perovskite and reducing its stability against halide segregation. Our work elucidates links between composition, ionic pathways, and halide segregation, and it facilitates the future engineering of phase-stable mixed-halide perovskites.
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Affiliation(s)
- Alexander J. Knight
- Department of Physics, Clarendon Laboratory,
University of Oxford, Parks Road, Oxford OX1 3PU,
United Kingdom
| | - Juliane Borchert
- Department of Physics, Clarendon Laboratory,
University of Oxford, Parks Road, Oxford OX1 3PU,
United Kingdom
| | - Robert D. J. Oliver
- Department of Physics, Clarendon Laboratory,
University of Oxford, Parks Road, Oxford OX1 3PU,
United Kingdom
| | - Jay B. Patel
- Department of Physics, Clarendon Laboratory,
University of Oxford, Parks Road, Oxford OX1 3PU,
United Kingdom
| | - Paolo G. Radaelli
- Department of Physics, Clarendon Laboratory,
University of Oxford, Parks Road, Oxford OX1 3PU,
United Kingdom
| | - Henry J. Snaith
- Department of Physics, Clarendon Laboratory,
University of Oxford, Parks Road, Oxford OX1 3PU,
United Kingdom
| | - Michael B. Johnston
- Department of Physics, Clarendon Laboratory,
University of Oxford, Parks Road, Oxford OX1 3PU,
United Kingdom
| | - Laura M. Herz
- Department of Physics, Clarendon Laboratory,
University of Oxford, Parks Road, Oxford OX1 3PU,
United Kingdom
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10
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Kim GY, Senocrate A, Wang Y, Moia D, Maier J. Photo-Effect on Ion Transport in Mixed Cation and Halide Perovskites and Implications for Photo-Demixing*. Angew Chem Int Ed Engl 2021; 60:820-826. [PMID: 32876999 PMCID: PMC7839519 DOI: 10.1002/anie.202005853] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Indexed: 11/24/2022]
Abstract
Lead halide perovskites are considered to be most promising photovoltaic materials. Highest efficiency and improved stability of perovskite solar cells have been achieved by using cation and anion mixtures. Experimental information on electronic and ionic charge carriers is key to evaluate device performance, as well as processes of photo-decomposition and photo-demixing which are observed in these materials. Here, we measure ionic and electronic transport properties and investigate various cation and anion substitutions with a special eye on their photo-ionic effect, following our previous study on CH3 NH3 PbI3 , where we found that light enhances not only electronic but also ionic conductivities. We find that this phenomenon is very sensitive to the nature of the halide, while the cationic substitutions are less relevant. Based on the observation that the ionic conductivity enhancement found for iodide perovskites is significantly weakened by bromide substitution, we provide a chemical rationale for the photo-demixing in mixed halide compositions.
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Affiliation(s)
- Gee Yeong Kim
- Physical Chemistry of SolidsMax Planck Institute for Solid State ResearchHeisenbergstrasse 170569StuttgartGermany
| | - Alessandro Senocrate
- Physical Chemistry of SolidsMax Planck Institute for Solid State ResearchHeisenbergstrasse 170569StuttgartGermany
| | - Ya‐Ru Wang
- Physical Chemistry of SolidsMax Planck Institute for Solid State ResearchHeisenbergstrasse 170569StuttgartGermany
| | - Davide Moia
- Physical Chemistry of SolidsMax Planck Institute for Solid State ResearchHeisenbergstrasse 170569StuttgartGermany
| | - Joachim Maier
- Physical Chemistry of SolidsMax Planck Institute for Solid State ResearchHeisenbergstrasse 170569StuttgartGermany
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11
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Kim GY, Senocrate A, Wang Y, Moia D, Maier J. Photo‐Effect on Ion Transport in Mixed Cation and Halide Perovskites and Implications for Photo‐Demixing**. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202005853] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Gee Yeong Kim
- Physical Chemistry of Solids Max Planck Institute for Solid State Research Heisenbergstrasse 1 70569 Stuttgart Germany
| | - Alessandro Senocrate
- Physical Chemistry of Solids Max Planck Institute for Solid State Research Heisenbergstrasse 1 70569 Stuttgart Germany
| | - Ya‐Ru Wang
- Physical Chemistry of Solids Max Planck Institute for Solid State Research Heisenbergstrasse 1 70569 Stuttgart Germany
| | - Davide Moia
- Physical Chemistry of Solids Max Planck Institute for Solid State Research Heisenbergstrasse 1 70569 Stuttgart Germany
| | - Joachim Maier
- Physical Chemistry of Solids Max Planck Institute for Solid State Research Heisenbergstrasse 1 70569 Stuttgart Germany
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12
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Yu X, Yan X, Xiao J, Ku Z, Zhong J, Li W, Huang F, Peng Y, Cheng YB. Interface modification effect on the performance of CsxFA1−xPbIyBr3−y perovskite solar cells fabricated by evaporation/spray-coating method. J Chem Phys 2020; 153:014706. [DOI: 10.1063/5.0012803] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Xinxin Yu
- State Key Lab of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, People’s Republic of China
| | - Xue Yan
- State Key Lab of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, People’s Republic of China
| | - Junyan Xiao
- School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, People’s Republic of China
| | - Zhiliang Ku
- State Key Lab of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, People’s Republic of China
| | - Jie Zhong
- State Key Lab of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, People’s Republic of China
| | - Wei Li
- State Key Lab of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, People’s Republic of China
| | - Fuzhi Huang
- State Key Lab of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, People’s Republic of China
| | - Yong Peng
- State Key Lab of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, People’s Republic of China
| | - Yi-Bing Cheng
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, People’s Republic of China
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13
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Funk H, Shargaieva O, Eljarrat A, Unger EL, Koch CT, Abou-Ras D. In Situ TEM Monitoring of Phase-Segregation in Inorganic Mixed Halide Perovskite. J Phys Chem Lett 2020; 11:4945-4950. [PMID: 32486642 DOI: 10.1021/acs.jpclett.0c01296] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Photoinduced phase separation, which limits the available band gap energies for photovoltaic applications, was reported for a range of mixed-halide perovskites. A microscopic understanding of the phase separation mechanism is still lacking but may be beneficial to rationalize limitations as well as enable the design of phase-stable perovskite semiconductors. In this letter, electron-beam-induced phase separations and transformations were investigated in a small crystallite of CsPb(Br0.8I0.2)3 by means of in situ high-resolution imaging in a transmission electron microscope. The acquired time series was evaluated using principal and independent component analysis to classify the structural change during the illumination by the electron beam. A more iodine-rich phase with the approximate composition of CsPb(Br0.6I0.4)3 was found to form at the edges of the particle, while a ternary pure bromide phase of CsPbBr3 remained at its center. These results provide an atomistic picture of in-grain phase segregation into iodide-rich phases at grain boundaries and bromide-rich phases in the interior of the grain.
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Affiliation(s)
- Hannah Funk
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Berlin, Germany
- Structure and Dynamics of Energy Materials, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin, Germany
| | - Oleksandra Shargaieva
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Berlin, Germany
- Young Investigator Group "Hybrid Materials Formation and Scaling", Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Kekuléstraße 5, 12489 Berlin, Germany
| | - Alberto Eljarrat
- Institut für Physik, Humboldt-Universität zu Berlin, Newtonstraße 15, 12489 Berlin, Germany
| | - Eva L Unger
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Berlin, Germany
- Young Investigator Group "Hybrid Materials Formation and Scaling", Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Kekuléstraße 5, 12489 Berlin, Germany
| | - Christoph T Koch
- Institut für Physik, Humboldt-Universität zu Berlin, Newtonstraße 15, 12489 Berlin, Germany
| | - Daniel Abou-Ras
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Berlin, Germany
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14
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Meng X, Chi K, Li Q, Cao Y, Song G, Liu B, Yang H, Fu W. Interfacial Modification of Mesoporous TiO 2 Films with PbI 2-Ethanolamine-Dimethyl Sulfoxide Solution for CsPbIBr 2 Perovskite Solar Cells. NANOMATERIALS 2020; 10:nano10050962. [PMID: 32443581 PMCID: PMC7325578 DOI: 10.3390/nano10050962] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 05/11/2020] [Accepted: 05/14/2020] [Indexed: 12/05/2022]
Abstract
As one of the most frequently-used electron-transporting materials, the mesoporous titanium dioxide (m-TiO2) film used in mesoporous structured perovskite solar cells (PSCs) can be employed for the scaffold of the perovskite film and as a pathway for electron transport, and the contact area between the perovskite and m-TiO2 directly determines the comprehensive performance of the PSCs. Because of the substandard interface combining quality between the all-inorganic perovskite CsPbIBr2 and m-TiO2, the development of the mesoporous structured CsPbIBr2 PSCs synthesized by the one-step method is severely limited. Here, we used a solution containing PbI2, monoethanolamine (EA) and dimethyl sulfoxide (DMSO) (PED) as the interfacial modifier to enhance the contact area and modify the m-TiO2/CsPbIBr2 contact characteristics. Comparatively, the performance of the solar device based on the PED-modified m-TiO2 layer has improved considerably, and its power conversion efficiency is up to 6.39%.
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Affiliation(s)
- Xianwei Meng
- State Key Laboratory of Superhard Materials, Jilin University, Changchun 130012, China; (X.M.); (H.Y.)
| | - Kailin Chi
- School of Science, Northeast Electric Power University, Jilin 132012, China; (K.C.); (G.S.); (B.L.)
| | - Qian Li
- Beijing Key Lab of Cryo-Biomedical Engineering and Key Lab of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, China;
| | - Yu Cao
- School of Electrical Engineering, Northeast Electric Power University, Jilin 132012, China;
| | - Gengxin Song
- School of Science, Northeast Electric Power University, Jilin 132012, China; (K.C.); (G.S.); (B.L.)
| | - Bao Liu
- School of Science, Northeast Electric Power University, Jilin 132012, China; (K.C.); (G.S.); (B.L.)
| | - Haibin Yang
- State Key Laboratory of Superhard Materials, Jilin University, Changchun 130012, China; (X.M.); (H.Y.)
| | - Wuyou Fu
- State Key Laboratory of Superhard Materials, Jilin University, Changchun 130012, China; (X.M.); (H.Y.)
- Correspondence: ; Tel.: +86-431-8516-8763-801; Fax: +86-431-8516-8763-801
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15
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Caputo M, Cefarin N, Radivo A, Demitri N, Gigli L, Plaisier JR, Panighel M, Di Santo G, Moretti S, Giglia A, Polentarutti M, De Angelis F, Mosconi E, Umari P, Tormen M, Goldoni A. Electronic structure of MAPbI 3 and MAPbCl 3: importance of band alignment. Sci Rep 2019; 9:15159. [PMID: 31641160 PMCID: PMC6805902 DOI: 10.1038/s41598-019-50108-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 08/28/2019] [Indexed: 12/02/2022] Open
Abstract
Since their first appearance, organic-inorganic perovskite absorbers have been capturing the attention of the scientific community. While high efficiency devices highlight the importance of band level alignment, very little is known on the origin of the strong n-doping character observed in the perovskite. Here, by means of a highly accurate photoemission study, we shed light on the energy alignment in perovskite-based devices. Our results suggest that the interaction with the substrate may be the driver for the observed doping in the perovskite samples.
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Affiliation(s)
- Marco Caputo
- Elettra - Sincrotrone Trieste, s.s. 14 Km 163.5 in Area Science Park, Basovizza (Trieste) 34149, Trieste, Italy.
| | - Nicola Cefarin
- IOM-CNR Lab. TASC, s.s. 14 Km 163.5 in Area Science Park, Basovizza (Trieste) 34149, Trieste, Italy
- Dipartimento di Fisica - Università di Trieste, via Valerio Trieste, Trieste, Italy
| | - Andrea Radivo
- Elettra - Sincrotrone Trieste, s.s. 14 Km 163.5 in Area Science Park, Basovizza (Trieste) 34149, Trieste, Italy
- IOM-CNR Lab. TASC, s.s. 14 Km 163.5 in Area Science Park, Basovizza (Trieste) 34149, Trieste, Italy
| | - Nicola Demitri
- Elettra - Sincrotrone Trieste, s.s. 14 Km 163.5 in Area Science Park, Basovizza (Trieste) 34149, Trieste, Italy
| | - Lara Gigli
- Elettra - Sincrotrone Trieste, s.s. 14 Km 163.5 in Area Science Park, Basovizza (Trieste) 34149, Trieste, Italy
| | - Jasper R Plaisier
- Elettra - Sincrotrone Trieste, s.s. 14 Km 163.5 in Area Science Park, Basovizza (Trieste) 34149, Trieste, Italy
| | - Mirco Panighel
- Elettra - Sincrotrone Trieste, s.s. 14 Km 163.5 in Area Science Park, Basovizza (Trieste) 34149, Trieste, Italy
- Dipartimento di Fisica - Università di Trieste, via Valerio Trieste, Trieste, Italy
| | - Giovanni Di Santo
- Elettra - Sincrotrone Trieste, s.s. 14 Km 163.5 in Area Science Park, Basovizza (Trieste) 34149, Trieste, Italy
| | - Sacha Moretti
- CNR - Institute of Atmospheric pollution Research - Sezione di Rende - c/o Polifunzionale - UNICAL 87036 Rende (CS), Rende, Italy
| | - Angelo Giglia
- IOM-CNR Lab. TASC, s.s. 14 Km 163.5 in Area Science Park, Basovizza (Trieste) 34149, Trieste, Italy
| | - Maurizio Polentarutti
- Elettra - Sincrotrone Trieste, s.s. 14 Km 163.5 in Area Science Park, Basovizza (Trieste) 34149, Trieste, Italy
| | - Filippo De Angelis
- Computational Laboratory for Hybrid/Organic Photovoltaics (CLHYO), CNR-ISTM, Via Elce di Sotto 8, I-06123, Perugia, Italy
- CompuNet, Istituto Italiano di Tecnologia, Via Morego 30, 16163, Genova, Italy
| | - Edoardo Mosconi
- Computational Laboratory for Hybrid/Organic Photovoltaics (CLHYO), CNR-ISTM, Via Elce di Sotto 8, I-06123, Perugia, Italy
- CompuNet, Istituto Italiano di Tecnologia, Via Morego 30, 16163, Genova, Italy
| | - Paolo Umari
- IOM-CNR Lab. TASC, s.s. 14 Km 163.5 in Area Science Park, Basovizza (Trieste) 34149, Trieste, Italy
- Dipartimento di Fisica e Astronomia - Università di Padova, via Marzolo, 35131, Padova, Italy
| | - Massimo Tormen
- IOM-CNR Lab. TASC, s.s. 14 Km 163.5 in Area Science Park, Basovizza (Trieste) 34149, Trieste, Italy
| | - Andrea Goldoni
- Elettra - Sincrotrone Trieste, s.s. 14 Km 163.5 in Area Science Park, Basovizza (Trieste) 34149, Trieste, Italy.
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16
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Lu J, Chen SC, Zheng Q. Defect passivation of CsPbI2Br perovskites through Zn(II) doping: toward efficient and stable solar cells. Sci China Chem 2019. [DOI: 10.1007/s11426-019-9486-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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17
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Tennyson EM, Roose B, Garrett JL, Gong C, Munday JN, Abate A, Leite MS. Cesium-Incorporated Triple Cation Perovskites Deliver Fully Reversible and Stable Nanoscale Voltage Response. ACS NANO 2019; 13:1538-1546. [PMID: 30586503 DOI: 10.1021/acsnano.8b07295] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Perovskite solar cells that incorporate small concentrations of Cs in their A-site have shown increased lifetime and improved device performance. Yet, the development of fully stable devices operating near the theoretical limit requires understanding how Cs influences perovskites' electrical properties at the nanoscale. Here, we determine how the chemical composition of three perovskites (MAPbBr3, MAPbI3, and Cs-mixed) affects their short- and long-term voltage stabilities, with <50 nm spatial resolution. We map an anomalous irreversible electrical signature on MAPbBr3 at the mesoscale, resulting in local V oc variations of ∼400 mV, and in entire grains with negative contribution to the V oc. These measurements prove the necessity of high spatial resolution mapping to elucidate the fundamental limitations of this emerging material. Conversely, we capture the fully reversible voltage response of Cs-mixed perovskites, composed by Cs0.06(MA0.17FA0.83)0.94Pb(I0.83Br0.17)3, demonstrating that the desired electrical output persists even at the nanoscale. The Cs-mixed material presents no spatial variation in V oc, as ion motion is restricted. Our results show that the nanoscale electrical behavior of the perovskites is intimately connected to their chemical composition and macroscopic response.
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Affiliation(s)
- Elizabeth M Tennyson
- Department of Materials Science and Engineering , University of Maryland , College Park , Maryland 20742 , United States
- Institute for Research in Electronics and Applied Physics , University of Maryland , College Park , Maryland 20742 , United States
| | - Bart Roose
- Cavendish Laboratory, Department of Physics , University of Cambridge , JJ Thomson Avenue , CB3 0HE Cambridge , United Kingdom
| | - Joseph L Garrett
- Institute for Research in Electronics and Applied Physics , University of Maryland , College Park , Maryland 20742 , United States
- Department of Physics , University of Maryland , College Park , Maryland 20742 , United States
| | - Chen Gong
- Department of Materials Science and Engineering , University of Maryland , College Park , Maryland 20742 , United States
- Institute for Research in Electronics and Applied Physics , University of Maryland , College Park , Maryland 20742 , United States
| | - Jeremy N Munday
- Institute for Research in Electronics and Applied Physics , University of Maryland , College Park , Maryland 20742 , United States
- Department of Electrical and Computer Engineering , University of Maryland , College Park , Maryland 20742 , United States
| | - Antonio Abate
- Helmholtz-Zentrum Berlin für Materialien und Energie , Kekuléstraße 5 , 12489 Berlin , Germany
- Department of Chemical, Materials and Production Engineering , University of Naples Federico II , Piazzale Tecchio 80 , 80125 Fuorigrotta, Naples , Italy
| | - Marina S Leite
- Department of Materials Science and Engineering , University of Maryland , College Park , Maryland 20742 , United States
- Institute for Research in Electronics and Applied Physics , University of Maryland , College Park , Maryland 20742 , United States
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18
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Bischak CG, Wong AB, Lin E, Limmer DT, Yang P, Ginsberg NS. Tunable Polaron Distortions Control the Extent of Halide Demixing in Lead Halide Perovskites. J Phys Chem Lett 2018; 9:3998-4005. [PMID: 29979045 DOI: 10.1021/acs.jpclett.8b01512] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Photoinduced phase separation in mixed halide perovskites emerges from their electro-mechanical properties and high ionic conductivities, resulting in photoinduced I--rich charge carrier traps that diminish photovoltaic performance. Whether photoinduced phase separation stems from the polycrystalline microstructure or is an intrinsic material property has been an open question. We investigate the nanoscale photoinduced behavior of single-crystal mixed Br-/I- methylammonium (MA+) lead halide perovskite (MAPb(Br xI1- x)3) nanoplates, eliminating effects from extended structural defects. Even in these nanoplates, we find that phase separation occurs, resulting in I--rich clusters that are nucleated stochastically and stabilized by polarons. Upon lowering the electron-phonon coupling strength by partially exchanging MA+ for Cs+, a phase-separated steady state is not reached, nevertheless transient I- clustering still occurs. Our results, supported by multiscale modeling, demonstrate that photoinduced phase separation is an intrinsic property of mixed halide perovskites, the extent and dynamics of which depends on the electron-phonon coupling strength.
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Affiliation(s)
- Connor G Bischak
- Department of Chemistry , University of California , Berkeley , California 94720 , United States
| | - Andrew B Wong
- Department of Chemistry , University of California , Berkeley , California 94720 , United States
| | - Elbert Lin
- Department of Chemistry , University of California , Berkeley , California 94720 , United States
| | - David T Limmer
- Department of Chemistry , University of California , Berkeley , California 94720 , United States
- Kavli Energy NanoScience Institute , Berkeley , California 94720 , United States
- Materials Science Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Peidong Yang
- Department of Chemistry , University of California , Berkeley , California 94720 , United States
- Kavli Energy NanoScience Institute , Berkeley , California 94720 , United States
- Materials Science Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
- Department of Materials Science and Engineering , University of California , Berkeley , California 94720 , United States
| | - Naomi S Ginsberg
- Department of Chemistry , University of California , Berkeley , California 94720 , United States
- Kavli Energy NanoScience Institute , Berkeley , California 94720 , United States
- Materials Science Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
- Molecular Biophysics and Integrated Bioimaging Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
- Department of Physics , University of California , Berkeley , California 94720 , United States
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