Optoelectronics of Lead-Free Antimony- and Bismuth-Based Metal Halides for Sensitive and Low-Noise Photodetection

Organic-inorganic hybrid halide perovskites have emerged as the most promising optoelectronic materials for next-generation solution-processed devices, primarily attributed to their distinctive properties such as cost-effectiveness, facile fabrication process, high light absorption coefficient, tunable bandgap, and relatively high charge carrier mobility. Nevertheless, the presence of Pb elements is inevitable in most high-performance perovskite optoelectronic devices, posing environmental pollution concerns and impeding their commercialization. In this study, two novel non-toxic bismuth- and antimony-based perovskite materials with environmentally conscious approaches are developed. Their structures and optoelectronic properties have been systematically characterized. Subsequently, photoconductive- and photodiode-type photodetectors are designed and fabricated. Notably, the photodiode configuration exhibits exceptionally low dark current and noise, superior detection sensitivity, fast response speed, and good device stability. Owing to these superior performance metrics, the devices demonstrate great potential for real applications. Furthermore, this study furnishes a theoretical framework and design perspectives for the solution-processed semiconductor materials. Two novel Bi- and Sb-based perovskite materials have been synthesized. The crystal structure and optoelectronic properties of the synthesized materials have been studied systematically. Photodetectors incorporating both photoconductor- and photodiodetype structures of these two materials have been designed. The fabricated photodiode devices demonstrated low noise, high specific detectivity, large linear dynamic range, and rapid response time, showing great potential for real applications. image