Lead-Free Ultra-Wide Direct Bandgap Perovskite EACaI3

Recently, perovskite-based light-emitting devices (LEDs) have been invested with near-infrared, red, green, and blue emissions. And, short-wavelength perovskite LEDs targeted at violet emission remain a significant challenge. Moreover, the majority of previously reported devices were focused on the lead-containing halide perovskites. In this research, for the first time, EACaI₃ (270 nm) was proposed as ultraviolet-C potential lead-free perovskite material with direct ultra-wide bandgap property with 0.03% imaginary part of phonon density of state. The perovskite EACaI₃ has dynamic stability and could be used for devices demonstrated with excellent working stability. These results suggest that the lead-free EACaI₃ are potentially attractive candidates for preparing environment-friendly and stable ultra-wide band gap device.