Recent advances in lead-free halide perovskites: from synthesis to applications

Lead-based halide perovskites have taken semiconductor optoelectronics research by storm owing to their impressive optical and optoelectronic properties, emerging as promising candidates for high-performance solar cells, transistors, light-emitting diodes (LEDs), photodetectors, and other devices. However, the toxicity of these perovskites significantly limits their large-scale application. Therefore, the development of lead-free halide perovskites without sacrificing device performance is highly desirable. Lead-free halide perovskites based on elements such as Sn, Ge, Bi, and Cu are considered suitable alternatives for different applications. Herein, we review the methods for the synthesis of lead-free halide perovskites and comprehensively summarize the latest progress on lead-free halide perovskites in solar cells, transistors, photodetectors, sensors, LEDs and other fields based on different alternative elements from the perspective of materials science and device physics. Moreover, the performance advantages and application potential of lead-free perovskite materials based on different elements are highlighted, and strategies to improve the performance and stability of lead-free halide optoelectronic devices are investigated. Simultaneously, future development directions such as perovskite-organic hybrid optoelectronic devices in this research field are proposed and discussed. This review provides a comprehensive perspective on the in-depth study of lead-free halide perovskites and provides valuable insights into the current research status of lead-free halide perovskite optoelectronic devices, which will promote the development and design of new structures and devices, thereby further improving the performance and stability of devices to meet different needs in practical applications. The recent progress and development directions in lead-free perovskites are summarized from the perspective of device physics and materials science.