Air-stable all inorganic green perovskite light emitting diodes based on ZnO/CsPbBr3/NiO heterojunction structure

Perovskite light emitting diodes (PeLEDs) now emerge as a promising new optoelectronic application field for these amazing semiconductors. However, most PeLEDs contain organic components, which make them unstable in the air. For fabricating the air-stable all inorganic green PeLEDs, we have designed green PeLEDs based on the ZnO/CsPbBr3/NiO heterojunction structure. The emission layer inorganic perovskite CsPbBr3 film with small grain sizes was prepared using a two-step method. The device exhibits a typical rectification behavior with turn-on voltage of ~ 3 V. The working mechanism of the device is discussed. The EL emission bands are narrow with small FWHM values. The continuous working air-stability was also monitored. The results reveal our PeLED can maintain a good color purity and a stable EL intensity when it works continuously in the air. Our present work suggests great potential for the development and practical commercial application of PeLEDs.