Synthesis of stable and lead-free all-inorganic metal halide perovskites

• Grant number: 21/11392-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2022
• End date: July 31, 2023
• Field of knowledge: Physical Sciences and Mathematics - Chemistry
• Principal Investigator: Laudemir Carlos Varanda
• Grantee: Stéphany de Oliveira Romera
• Host Institution: Instituto de Química de São Carlos (IQSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil

Abstract

The development or improvement appeal for new energy matrices has been driving several areas of science and technology. In this context, chemistry plays a key role in the sustainable development of new technologies, materials, and processes, called environmentally friendly or green. The solar into electrical energy conversion has been standing out in the last decade and photovoltaic processes had a significant hopping with the use of systems and devices involving perovskites. In recent years, however, its growth remains slow concerning the conversion efficiency and stability increases. Hybrid perovskites (organic-inorganic) containing lead proved to be promising materials, but over time, they are unstable and the presence of lead makes the material with low sustainability. New all-inorganic lead-free perovskite materials have emerged as an alternative, but much still needs to be done regarding their stability and efficiency. It is necessary to overcome the challenge of obtaining materials and devices with high efficiency, stability, and sustainability. This research project aims to explore the synthesis of all-inorganic lead-free perovskite nanocrystals based on the structure Cs8AuIII4MIIIX23, where M = In3+, Sb3+, Bi3+; and X = Cl-, Br-, I-. The focus of the proposal is centered on systems with high uniformity of shape and size, and to adjust them to present a narrow size distribution and structure correlation (high crystallinity and chemical stability). This enhanced material could be contributing to obtaining the desired optoelectronic properties. Two different methodologies will be used (in aqueous and non-aqueous media) for comparative purposes. In the end, it is expected to obtain high-quality all-inorganic perovskite nanoparticles synthesis by sustainable routes that prove viable for use in photovoltaic devices.(AU)