Research progress of ABX-type lead-free perovskites for optoelectronic applications: materials and devices.

In recent years, lead halide perovskite materials have attracted great interest and are widely used in solar cells and light-emitting devices due to their high photoelectronic quantum yield, high color purity, high defect tolerance, long diffusion length, high carrier mobility, and bandgap tunability. However, the application of lead halide perovskites is limited due to the presence of Pb, making lead-free perovskites an important substitute due to their same crystal structure and similar properties. Although some reports have been made on lead-free perovskite materials, there are still great challenges to realize their application due to their poor stability, easy phase transition, and low photoelectric conversion efficiency.