Exploring the Structural Stability of Lead-Free Halide Perovskites via GIWAXS for Sustainable Optoelectronic Devices

Halide perovskites have gained prominence as promising materials in optoelectronic applications; however, their reliance on harsh chemical synthesis methods and their degradation in the presence of temperature, oxygen, and other environmental factors pose challenges for device implementation. On the other hand, recent advancements in high entropy (HE) materials offer new paths of tunability and functionality in the semiconductor field by combining different elements showing great promise as a new environmentally friendly material. This study explores vacancy-ordered perovskites with alternative B-site compositions, as environmentally friendly and more stable substitutes for lead-based perovskites. Our research focuses on synthesizing and characterizing various lead-free perovskite materials, including Cs₂HfCl₆, Cs₂TeCl₆, and Cs₂ZrCl₆. We aim to employ GIWAXS ex-situ and in-situ to investigate these materials' structural stability and degradation under varying environmental conditions (temperature and atmosphere). The results will elucidate how different synthesis methods and deposition impact the structure and stability. The samples we will analyze are on their way to synthesizing HE perovskites, and understanding the properties and stability of their building blocks will enable HE production, providing insights into their potential for future commercial applications in perovskite optoelectronic technologies such as LEDs, X-ray detectors, and photodetectors.