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Zhao C, Cazorla C, Zhang X, Huang H, Zhao X, Li D, Shi J, Zhao Q, Ma W, Yuan J. Fast Organic Cation Exchange in Colloidal Perovskite Quantum Dots toward Functional Optoelectronic Applications. J Am Chem Soc 2024; 146:4913-4921. [PMID: 38319594 DOI: 10.1021/jacs.3c14000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2024]
Abstract
Colloidal quantum dots with lower surface ligand density are desired for preparing the active layer for photovoltaic, lighting, and other potential optoelectronic applications. In emerging perovskite quantum dots (PQDs), the diffusion of cations is thought to have a high energy barrier, relative to that of halide anions. Herein, we investigate the fast cross cation exchange approach in colloidal lead triiodide PQDs containing methylammonium (MA+) and formamidinium (FA+) organic cations, which exhibits a significantly lower exchange barrier than inorganic cesium (Cs+)-FA+ and Cs+-MA+ systems. First-principles calculations further suggest that the fast internal cation diffusion arises due to a lowering in structural distortions and the consequent decline in attractive cation-cation and cation-anion interactions in the presence of organic cation vacancies in mixed MA+-FA+ PQDs. Combining both experimental and theoretical evidence, we propose a vacancy-assisted exchange model to understand the impact of structural features and intermolecular interaction in PQDs with fewer surface ligands. Finally, for a realistic outcome, the as-prepared mixed-cation PQDs display better photostability and can be directly applied for one-step coated photovoltaic and photodetector devices, achieving a high photovoltaic efficiency of 15.05% using MA0.5FA0.5PbI3 PQDs and more precisely tunable detective spectral response from visible to near-infrared regions.
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Affiliation(s)
- Chenyu Zhao
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu 215123, P. R. China
- Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou 215123, Jiangsu, P. R. China
| | - Claudio Cazorla
- Departament de Física, Universitat Politècnica de Catalunya, Campus Nord B4-B5, 08034 Barcelona, Spain
| | - Xuliang Zhang
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu 215123, P. R. China
- Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou, Jiangsu 215123, P. R. China
| | - Hehe Huang
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu 215123, P. R. China
- Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou 215123, Jiangsu, P. R. China
| | - Xinyu Zhao
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu 215123, P. R. China
- Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou 215123, Jiangsu, P. R. China
| | - Du Li
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu 215123, P. R. China
- Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou 215123, Jiangsu, P. R. China
| | - Junwei Shi
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu 215123, P. R. China
| | - Qian Zhao
- School of Materials Science and Engineering, Nankai University, Tianjin 300350, P. R. China
| | - Wanli Ma
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu 215123, P. R. China
- Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou, Jiangsu 215123, P. R. China
| | - Jianyu Yuan
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu 215123, P. R. China
- Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou 215123, Jiangsu, P. R. China
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2
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Minussi FB, Silva RM, Araújo EB. Composition-Property Relations for GA x FA y MA 1- x - y PbI 3 Perovskites. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2305054. [PMID: 37803390 DOI: 10.1002/smll.202305054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 09/21/2023] [Indexed: 10/08/2023]
Abstract
Halide perovskites are materials for diverse optoelectronic applications owing to a combination of factors, including their compositional flexibility. A major source of this diversity of compositions comes from the use of mixed organic cations in the A-site of such compounds to form solid solutions. Many organic cations are possible for this purpose. Although significant progress is made over years of intensive research, the determination of systematic relationships between the compositions and properties of halide perovskites is not exploited accordingly. Using the MAPbI3 prototype, a wide range of compositions substituted by formamidinium (FA+ ) and guanidinium (GA+ ) cations are studied. From a detailed collection of experimental data and results reported in the literature, heat maps correlating the composition of GAx FAy MA1- x - y PbI3 solid solutions with phase transition temperatures, dielectric permittivity, and activation energies are constructed. Considering the characteristics of organic cations, namely their sizes, dipole moments, and the number of N─H bonds, it is possible to interpret the heat maps as consequences of these characteristics. This work brings a systematization of how obtaining specific properties of halide perovskites might be possible by customizing the characteristics of the A-site organic cations.
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Affiliation(s)
- Fernando Brondani Minussi
- Department of Physics and Chemistry, São Paulo State University, Ilha Solteira, SP, 15385-000, Brazil
| | - Rogério Marcos Silva
- Department of Electrical Engineering, São Paulo State University, Ilha Solteira, SP, 15385-000, Brazil
| | - Eudes Borges Araújo
- Department of Physics and Chemistry, São Paulo State University, Ilha Solteira, SP, 15385-000, Brazil
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3
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Crawford ML, Sadighian JC, Hassan Y, Sadhanala A, Nawab L, Wong CY. Formation of Iodide-Rich Domains During Halide Segregation in Lead-Halide Perovskite Nanocrystals. J Phys Chem Lett 2023; 14:8962-8969. [PMID: 37772502 DOI: 10.1021/acs.jpclett.3c02068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/30/2023]
Abstract
Mixed iodide-bromide methylammonium lead perovskite (MAPbIxBr3-x) nanocrystals (NCs) hold promise for use in light-emitting applications owing to the size- and composition-tunability of their bandgap. However, the segregation of halides during light exposure causes their band gaps to become unstable and narrow. Here, we use transient absorption spectroscopy to track excited-state dynamics during photoinduced halide segregation. The Auger recombination dynamics are observed to accelerate as the bandgap narrows, suggesting enhanced electron-hole overlap. We simulate the motion of iodide within the NC and estimate the evolving bandgap and electron-hole overlap during two possible mechanisms of halide segregation. Our results support a segregation mechanism in which iodide anions form a domain within the NC, rather than a mechanism in which iodide anions independently segregate toward the NC surface. Such mechanistic insight will contribute to future NC bandgap stabilization strategies.
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Affiliation(s)
- Michael L Crawford
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97405, United States
| | - James C Sadighian
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97405, United States
| | - Yasser Hassan
- Department of Chemistry and Earth Sciences, College of Arts and Sciences, Qatar University, PO Box: 2713, Doha, Qatar
| | - Aditya Sadhanala
- Centre for Nano Science and Engineering, Indian Institute of Science, Bangalore 560012, India
| | - Laila Nawab
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97405, United States
| | - Cathy Y Wong
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97405, United States
- Oregon Center for Optical, Molecular, and Quantum Science, University of Oregon, Eugene, Oregon 97405, United States
- Materials Science Institute, University of Oregon, Eugene, Oregon 97405, United States
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4
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Moaddeli M, Kanani M, Grünebohm A. Electronic and structural properties of mixed-cation hybrid perovskites studied using an efficient spin-orbit included DFT-1/2 approach. Phys Chem Chem Phys 2023; 25:25511-25525. [PMID: 37712408 DOI: 10.1039/d3cp02472e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/16/2023]
Abstract
Fundamental understanding and optimization of the emerging mixed organic-inorganic hybrid perovskites for solar cells require multiscale modeling starting from ab initio quantum mechanics methods. Particularly, it is important to correctly predict the structural and electronic properties such as phase stability, lattice parameters, band gaps, and band structures. Although density functional theory is the method of choice to address these properties and generate the input for subsequent multiscale, high-throughput, and data-driven approaches, standard exchange correlation functionals fail to reproduce the bandgap, particularly if spin-orbit coupling (SOC) is correctly taken into account. While many SOC-included hybrid functionals suffer from low transferability between different molecular ions and are computationally costly, we propose an efficient multistep simulation protocol based on the DFT-1/2 method. We apply this approach to APbI3 with A: FA, MA, Cs, and systems with mixed cations and show how the choice of the A-cation modifies the Pb-I scaffold and the hydrogen bonding and discuss their interplay with structural stability. Furthermore, band gaps, band structures, Rashba band splitting, Born effective charges as well as partial density of states (PDOS) are compared for different cases w/wo the SOC effect and the DFT-1/2 approach.
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Affiliation(s)
- Mohammad Moaddeli
- Department of Materials Science and Engineering, School of Engineering, Shiraz University, Shiraz, Iran.
- Solar Energy Technology Development Center, Shiraz University, Shiraz, Iran
| | - Mansour Kanani
- Department of Materials Science and Engineering, School of Engineering, Shiraz University, Shiraz, Iran.
- Solar Energy Technology Development Center, Shiraz University, Shiraz, Iran
| | - Anna Grünebohm
- Interdisciplinary Centre for Advanced Materials Simulation (ICAMS) and Center for Interface-Dominated High Performance Materials (ZGH), Ruhr-University Bochum, Universitätsstr 150, 44801 Bochum, Germany
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5
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Garrote-Márquez A, Lodeiro L, Suresh R, Cruz Hernández N, Grau-Crespo R, Menéndez-Proupin E. Hydrogen Bonds in Lead Halide Perovskites: Insights from Ab Initio Molecular Dynamics. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2023; 127:15901-15910. [PMID: 37609385 PMCID: PMC10440809 DOI: 10.1021/acs.jpcc.3c02376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 07/12/2023] [Indexed: 08/24/2023]
Abstract
Hydrogen bonds (HBs) play an important role in the rotational dynamics of organic cations in hybrid organic/inorganic halide perovskites, thus affecting the structural and electronic properties of the perovskites. However, the properties and even the existence of HBs in these perovskites are not well established. In this study, we investigate HBs in perovskites MAPbBr3 (MA+ = CH3NH3+), FAPbI3 (FA+ = CH(NH2)2+), and their solid solution with composition (FAPbI3)7/8(MAPbBr3)1/8, using ab initio molecular dynamics and electronic structure calculations. We consider HBs donated by X-H fragments (X = N and C) of the organic cations and accepted by the halides (Y = Br and I) and characterize their properties based on pair distribution functions and on a combined distribution function of the hydrogen-acceptor distance with the donor-hydrogen-acceptor angle. By analyzing these functions, we establish geometrical criteria for HB existence based on the hydrogen-acceptor (H-Y) distance and donor-hydrogen-acceptor angle (X-H-Y). The distance condition is defined as d(H - Y) < 3 Å for N-H-donated HBs and d(H - Y) < 4 Å for C-H-donated HBs. The angular condition is 135° < (X - H - Y) < 180° for both types of HBs. A HB is considered to be formed when both angular and distance conditions are simultaneously satisfied. At the simulated temperature (350 K), the HBs dynamically break and form. We compute the time correlation functions of HB existence and HB lifetimes, which range between 0.1 and 0.3 ps at that temperature. The analysis of HB lifetimes indicates that N-H-Br bonds are relatively stronger than N-H-I bonds, while C-H-Y bonds are weaker, with a minimal influence from the halide and cation. To evaluate the impact of HBs on the vibrational spectra, we present the power spectrum in the region of N-H and C-H stretching modes, comparing them with the normal mode frequencies of isolated cations. We show that the peaks associated with N-H stretching modes in perovskites are redshifted and asymmetrically deformed, while the C-H peaks do not exhibit these effects.
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Affiliation(s)
- Alejandro Garrote-Márquez
- Departamento
de Física Aplicada I, Escuela Politécnica Superior, Universidad de Sevilla, Seville E-41011, Spain
| | - Lucas Lodeiro
- Departamento
de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Santiago, Ñuñoa 7800003, Chile
| | - Rahul Suresh
- Departamento
de Física Aplicada I, Escuela Politécnica Superior, Universidad de Sevilla, Seville E-41011, Spain
- International
Research Center of Spectroscopy and Quantum Chemistry - IRC SQC, Siberian Federal University, 79 Svobodny pr., 660041 Krasnoyarsk, Russia
| | - Norge Cruz Hernández
- Departamento
de Física Aplicada I, Escuela Politécnica Superior, Universidad de Sevilla, Seville E-41011, Spain
| | - Ricardo Grau-Crespo
- Department
of Chemistry, Whiteknights, University of
Reading, Reading RG6 6DX, UK
| | - Eduardo Menéndez-Proupin
- Departamento
de Física Aplicada I, Escuela Politécnica Superior, Universidad de Sevilla, Seville E-41011, Spain
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6
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Varadwaj PR, Varadwaj A, Marques HM, Yamashita K. Methylammonium Tetrel Halide Perovskite Ion Pairs and Their Dimers: The Interplay between the Hydrogen-, Pnictogen- and Tetrel-Bonding Interactions. Int J Mol Sci 2023; 24:10554. [PMID: 37445738 DOI: 10.3390/ijms241310554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 06/12/2023] [Accepted: 06/14/2023] [Indexed: 07/15/2023] Open
Abstract
The structural stability of the extensively studied organic-inorganic hybrid methylammonium tetrel halide perovskite semiconductors, MATtX3 (MA = CH3NH3+; Tt = Ge, Sn, Pb; X = Cl, Br, I), arises as a result of non-covalent interactions between an organic cation (CH3NH3+) and an inorganic anion (TtX3-). However, the basic understanding of the underlying chemical bonding interactions in these systems that link the ionic moieties together in complex configurations is still limited. In this study, ion pair models constituting the organic and inorganic ions were regarded as the repeating units of periodic crystal systems and density functional theory simulations were performed to elucidate the nature of the non-covalent interactions between them. It is demonstrated that not only the charge-assisted N-H···X and C-H···X hydrogen bonds but also the C-N···X pnictogen bonds interact to stabilize the ion pairs and to define their geometries in the gas phase. Similar interactions are also responsible for the formation of crystalline MATtX3 in the low-temperature phase, some of which have been delineated in previous studies. In contrast, the Tt···X tetrel bonding interactions, which are hidden as coordinate bonds in the crystals, play a vital role in holding the inorganic anionic moieties (TtX3-) together. We have demonstrated that each Tt in each [CH3NH3+•TtX3-] ion pair has the capacity to donate three tetrel (σ-hole) bonds to the halides of three nearest neighbor TtX3- units, thus causing the emergence of an infinite array of 3D TtX64- octahedra in the crystalline phase. The TtX44- octahedra are corner-shared to form cage-like inorganic frameworks that host the organic cation, leading to the formation of functional tetrel halide perovskite materials that have outstanding optoelectronic properties in the solid state. We harnessed the results using the quantum theory of atoms in molecules, natural bond orbital, molecular electrostatic surface potential and independent gradient models to validate these conclusions.
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Affiliation(s)
- Pradeep R Varadwaj
- Department of Chemical System Engineering, School of Engineering, The University of Tokyo, 7-3-1, Tokyo 113-8656, Japan
- School of Chemistry, Molecular Sciences Institute, University of the Witwatersrand, Johannesburg 2050, South Africa
| | - Arpita Varadwaj
- Department of Chemical System Engineering, School of Engineering, The University of Tokyo, 7-3-1, Tokyo 113-8656, Japan
| | - Helder M Marques
- School of Chemistry, Molecular Sciences Institute, University of the Witwatersrand, Johannesburg 2050, South Africa
| | - Koichi Yamashita
- Department of Chemical System Engineering, School of Engineering, The University of Tokyo, 7-3-1, Tokyo 113-8656, Japan
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7
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Wu J, Chen J, Wang H. Phase Transition Kinetics of MAPbI 3 for Tetragonal-to-Orthorhombic Evolution. JACS AU 2023; 3:1205-1212. [PMID: 37124306 PMCID: PMC10131189 DOI: 10.1021/jacsau.3c00060] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Revised: 03/07/2023] [Accepted: 03/14/2023] [Indexed: 05/03/2023]
Abstract
Despite the commonly observed phase-instability-induced photovoltaic degradation of MAPbI3, the phase transition kinetics at the atomic level remains elusive. Herein, by developing a stepwise NEB method, we clarify a nonsynergistic minimum-energy pathway for the tetragonal-to-orthorhombic phase transition. It is kinetically driven by the tilting of PbI6 4- that induces a spontaneous small rotation of adjoining MA+ and ends with stepwise ∼110° reorientations of two nonadjacent MA+ enabled by the cavity expansion. Compared to the common concerted mechanism, this process gives a low barrier of 0.08 eV/unit, demonstrating the easiness of the transition at extremely low temperatures and the importance of rotational entropies in regulating transition at elevated temperatures. With an explicit phase transition mechanism, we explore the structure-induced property response and reveal that introducing even low content of large-sized organic cations could help maintain the quasi-stable low-temperature performance of MAPbI3 solar cells.
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8
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Sterling CM, Kamal C, García-Fernández A, Man GJ, Svanström S, Nayak PK, Butorin SM, Rensmo H, Cappel UB, Odelius M. Electronic Structure and Chemical Bonding in Methylammonium Lead Triiodide and Its Precursor Methylammonium Iodide. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2022; 126:20143-20154. [PMID: 36483685 PMCID: PMC9720748 DOI: 10.1021/acs.jpcc.2c06782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 11/01/2022] [Indexed: 06/17/2023]
Abstract
A detailed examination of the electronic structures of methylammonium lead triiodide (MAPI) and methylammonium iodide (MAI) is performed with ab initio molecular dynamics (AIMD) simulations based on density functional theory, and the theoretical results are compared to experimental probes. The occupied valence bands of a MAPI single crystal and MAI powder are probed with X-ray photoelectron spectroscopy, and the conduction bands are probed from the perspective of nitrogen K-edge X-ray absorption spectroscopy. Combined, the theoretical simulations and the two experimental techniques allow for a dissection of the electronic structure unveiling the nature of chemical bonding in MAPI and MAI. Here, we show that the difference in band gap between MAPI and MAI is caused chiefly by interactions between iodine and lead but also weaker interactions with the MA+ counterions. Spatial decomposition of the iodine p levels allows for analysis of Pb-I σ bonds and π interactions, which contribute to this effect with the involvement of the Pb 6p levels. Differences in hydrogen bonding between the two materials, seen in the AIMD simulations, are reflected in nitrogen valence orbital composition and in nitrogen K-edge X-ray absorption spectra.
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Affiliation(s)
- Cody M. Sterling
- Department
of Physics, Stockholm University, AlbaNova
University Center, SE-106 91Stockholm, Sweden
| | - Chinnathambi Kamal
- Department
of Physics, Stockholm University, AlbaNova
University Center, SE-106 91Stockholm, Sweden
- Theory
and Simulations Laboratory, Theoretical and Computational Physics
Section, Raja Ramanna Centre for Advanced
Technology, Indore452013, India
- Homi
Bhabha National Institute, Training School
Complex, Anushakti Nagar, Mumbai400094, India
| | - Alberto García-Fernández
- Division
of Applied Physical Chemistry, Department of Chemistry, KTH - Royal Institute of Technology, SE-100 44Stockholm, Sweden
| | - Gabriel J. Man
- Condensed
Matter Physics of Energy Materials, Division of X-ray Photon Science,
Department of Physics and Astronomy, Uppsala
University, Box 516, SE-75121Uppsala, Sweden
- GJM
Scientific
Consulting, Fort Lee, New Jersey07024, United States
| | - Sebastian Svanström
- Condensed
Matter Physics of Energy Materials, Division of X-ray Photon Science,
Department of Physics and Astronomy, Uppsala
University, Box 516, SE-75121Uppsala, Sweden
| | - Pabitra K. Nayak
- Tata
Institute of Fundamental Research, 36/P, Gopanpally Village, Serilingampally Mandal, Ranga Reddy District, Hyderabad500046, India
| | - Sergei M. Butorin
- Condensed
Matter Physics of Energy Materials, Division of X-ray Photon Science,
Department of Physics and Astronomy, Uppsala
University, Box 516, SE-75121Uppsala, Sweden
| | - Håkan Rensmo
- Condensed
Matter Physics of Energy Materials, Division of X-ray Photon Science,
Department of Physics and Astronomy, Uppsala
University, Box 516, SE-75121Uppsala, Sweden
| | - Ute B. Cappel
- Division
of Applied Physical Chemistry, Department of Chemistry, KTH - Royal Institute of Technology, SE-100 44Stockholm, Sweden
| | - Michael Odelius
- Department
of Physics, Stockholm University, AlbaNova
University Center, SE-106 91Stockholm, Sweden
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9
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Erbing A, Philippe B, Park BW, Cappel UB, Rensmo H, Odelius M. Spatial Microheterogeneity in the Valence Band of Mixed Halide Hybrid Perovskite Materials. Chem Sci 2022; 13:9285-9294. [PMID: 36093010 PMCID: PMC9384462 DOI: 10.1039/d2sc03440a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 07/18/2022] [Indexed: 11/23/2022] Open
Abstract
The valence band of lead halide hybrid perovskites with a mixed I/Br composition is investigated using electronic structure calculations and complementarily probed with hard X-ray photoelectron spectroscopy. In the latter, we used high photon energies giving element sensitivity to the heavy lead and halide ions and we observe distinct trends in the valence band as a function of the I : Br ratio. Through electronic structure calculations, we show that the spectral trends with overall composition can be understood in terms of variations in the local environment of neighboring halide ions. From the computational model supported by the experimental evidence, a picture of the microheterogeneity in the valence band maximum emerges. The microheterogeneity in the valence band suggests that additional charge transport mechanisms might be active in lead mixed halide hybrid perovskites, which could be described in terms of percolation pathways. Microheterogeneity in valence band maximum of hybrid perovskites with mixed I/Br composition. Theoretical calculations show that trends in hard X-ray photoelectron spectroscopy with overall composition are related to variations in local environment.![]()
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Affiliation(s)
- Axel Erbing
- Department of Physics, Stockholm University, AlbaNova University Center SE-106 91 Stockholm Sweden +46 8 5537 8601 +46 8 5537 8713
| | - Bertrand Philippe
- Department of Physics and Astronomy, Uppsala University Box 516 SE-751 20 Uppsala Sweden
| | - Byung-Wook Park
- Department of Physics and Astronomy, Uppsala University Box 516 SE-751 20 Uppsala Sweden
- Department of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology 50 UNIST-gil, Eonyang-eup, Ulju-gun Ulsan 44919 Korea
| | - Ute B Cappel
- Division of Applied Physical Chemistry, Department of Chemistry, KTH Royal Institute of Technology SE-100 44 Stockholm Sweden
| | - Håkan Rensmo
- Department of Physics and Astronomy, Uppsala University Box 516 SE-751 20 Uppsala Sweden
| | - Michael Odelius
- Department of Physics, Stockholm University, AlbaNova University Center SE-106 91 Stockholm Sweden +46 8 5537 8601 +46 8 5537 8713
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10
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Kamal C, Hauschild D, Seitz L, Steininger R, Yang W, Heske C, Weinhardt L, Odelius M. Coupling Methylammonium and Formamidinium Cations with Halide Anions: Hybrid Orbitals, Hydrogen Bonding, and the Role of Dynamics. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2021; 125:25917-25926. [PMID: 34868447 PMCID: PMC8634158 DOI: 10.1021/acs.jpcc.1c08932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 10/27/2021] [Indexed: 06/13/2023]
Abstract
The electronic structures of four precursors for organic-inorganic hybrid perovskites, namely, methylammonium chloride and iodide, as well as formamidinium bromide and iodide, are investigated by X-ray emission (XE) spectroscopy at the carbon and nitrogen K-edges. The XE spectra are analyzed based on density functional theory calculations. We simulate the XE spectra at the Kohn-Sham level for ground-state geometries and carry out detailed analyses of the molecular orbitals and the electronic density of states to give a thorough understanding of the spectra. Major parts of the spectra can be described by the model of the corresponding isolated organic cation, whereas high-emission energy peaks in the nitrogen K-edge XE spectra arise from electronic transitions involving hybrids of the molecular and atomic orbitals of the cations and halides, respectively. We find that the interaction of the methylammonium cation is stronger with the chlorine than with the iodine anion. Furthermore, our detailed theoretical analysis highlights the strong influence of ultrafast proton dynamics in the core-excited states, which is an intrinsic effect of the XE process. The inclusion of this effect is necessary for an accurate description of the experimental nitrogen K-edge X-ray emission spectra and gives information on the hydrogen-bonding strengths in the different precursor materials.
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Affiliation(s)
- Chinnathambi Kamal
- Department
of Physics, Stockholm University, AlbaNova
University Center, SE-106 91 Stockholm, Sweden
- Theory
and Simulations Laboratory, HRDS, Raja Ramanna Centre for Advanced
Technology, Indore 452013, India
- Homi
Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 400094, India
| | - Dirk Hauschild
- Institute
for Photon Science and Synchrotron Radiation (IPS), Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen, Germany
- Institute
for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology (KIT), 76128 Karlsruhe, Germany
- Department
of Chemistry and Biochemistry, University
of Nevada Las Vegas (UNLV), Las
Vegas, Nevada 89154-4003, United States
| | - Linsey Seitz
- Institute
for Photon Science and Synchrotron Radiation (IPS), Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen, Germany
- Department
of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - Ralph Steininger
- Institute
for Photon Science and Synchrotron Radiation (IPS), Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen, Germany
| | - Wanli Yang
- Advanced
Light Source (ALS), Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Clemens Heske
- Institute
for Photon Science and Synchrotron Radiation (IPS), Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen, Germany
- Institute
for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology (KIT), 76128 Karlsruhe, Germany
- Department
of Chemistry and Biochemistry, University
of Nevada Las Vegas (UNLV), Las
Vegas, Nevada 89154-4003, United States
| | - Lothar Weinhardt
- Institute
for Photon Science and Synchrotron Radiation (IPS), Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen, Germany
- Institute
for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology (KIT), 76128 Karlsruhe, Germany
- Department
of Chemistry and Biochemistry, University
of Nevada Las Vegas (UNLV), Las
Vegas, Nevada 89154-4003, United States
| | - Michael Odelius
- Department
of Physics, Stockholm University, AlbaNova
University Center, SE-106 91 Stockholm, Sweden
| |
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