Chemistry Weekly Seminar- Renita D'Souza, PHD Candidate

Title

Stability of lead halide perovskites analyzed using in situ and operando grazing incidence wide-angle scattering experiments

Abstract

Lead halide perovskites have emerged as promising materials for next-generation optoelectronic applications, including solar cells, light-emitting diodes, and photodetectors, owing to their remarkable optoelectronic properties. With perovskite solar cells now achieving record efficiencies of 26.1%, the potential for commercial adoption is becoming increasingly tangible. However, the long-term stability of these materials remains a critical hurdle, as environmental factors such as moisture, heat, and radiation significantly impact their performance and durability.

This seminar will address my doctoral research, which focuses on addressing these stability challenges through comprehensive studies of lead halide perovskites under various environmental stressors. By utilizing in-situ grazing incidence wide-angle X-ray scattering (GIWAXS), the structural evolution of lead halide perovskite films when exposed to controlled humidity levels (0%, 40%, and 80% relative humidity) and ionizing radiation were investigated. Furthermore, to evaluate the effects of external environmental stressors on an operating solar cell, operando GIWAXS experiments were conducted under varying humidity conditions and elevated temperatures, providing crucial insights into the mechanisms of moisture-induced and thermal degradation of the solar cells. These accelerated aging studies offer a deeper understanding of how perovskite materials respond to real-world operating conditions and the key findings of the research will be discussed in the seminar.