Synthesis and physical properties of 0D and 2D halide perovskites

• Grant number: 21/10585-2
• Support type: Scholarships abroad - Research Internship - Doctorate (Direct)
• Effective date (Start): May 02, 2022
• Effective date (End): May 01, 2023
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal researcher: José Antonio Souza
• Grantee: Ariany Bonadio
• Supervisor abroad: Zhiqun Lin
• Home Institution: Centro de Ciências Naturais e Humanas (CCNH). Universidade Federal do ABC (UFABC). Ministério da Educação (Brasil). Santo André , SP, Brazil
• Research place: Georgia Institute of Technology, United States
• Associated to the scholarship: 18/14181-0 - Synthesis, characterization and computational simulation of hybrid APbX3 (a = CS and CH3NH3; X = i, CL e Br) perovskites, BP.DD

Abstract

Light-harvesting 3D organic-inorganic hybrid halide perovskites ABX3 have been attracting considerable attention due to their excellent photovoltaic performance and optoelectronic properties. Tuning in their electronic and crystal structures and photoelectric conductivity is at the heart of idealization of new materials, novel functionalities and/or improving the efficiency of optoelectronic devices. The important physical properties include suitable and adjustable band gaps, low exciton binding energy, very large optical absorption coefficients across the visible solar spectrum, long hole-electron diffusion length leading to efficient charge separation/collection, and high defect tolerance. Indeed, perovskite-based solar cells display high efficiency to convert solar energy into electricity, with a power conversion efficiency (PCE) exceeding 25%. However, despite the great progress in efficiency, the major drawbacks of the hybrid halide perovskites are the instability under ambient conditions and the toxicity of lead. Compared with the conventional 3D perovskite ABX3, the low-dimensional family exhibits better environmental stability and more varied compositions, electronic and crystal structures. In this project, we intend to obtain a better understanding on the synthesis, chemical, and physical properties of low dimensional 0D of the family A4BX6 and 2D organic-inorganic halide perovskites with general formula (OM)2An-1BnX3n+1 (n = 1, 2, 3, 4...), where OM is organic molecules, A is monovalent cation, B is a divalent metal cation, X is a halide anion, and n represents the number of [BX6]4- octahedral layers. The variation of dimensionality, organic cation, and the number of layers in the 2D structure can lead to the change of crystal structure, chemical and physical properties which offer a broad opportunity for materials and physical phenomenon discoveries and new technological applications. We intend to study the electronic and optical properties of these low-D perovskites separately and also placed on the top of 3D films. This is an effective approach to obtain more knowledge and insight for designing new perovskite devices. In this scenario, the 2D layered perovskites will be used as a protective layer for the 3D absorber in solar cell devices to improve efficiency and stability. (AU)