White LED based on CsPbBr3 nanocrystal phosphors via a facile two-step solution synthesis route

Abstract

All-inorganic CsPbBr3 perovskite nanocrystals with mean size of ∼300 nm were synthesized via a facile two-step solution synthesis route. High-resolution transmission electron microscopy and X-ray diffraction characterizations confirm the as-prepared CsPbBr3 nanoparticles are single-crystals with good crystallinity, although a CsPb2Br5 impure phase also exists in the final product. Power-/temperature-dependent and time-resolved photoluminescence measurements reveal the notable and stable excitonic emission feature of these CsPbBr3 nanocrystals. As a proof-of-concept demonstration, a LED with p-GaN/n-ZnO heterojunction as blue-violet excitation chip and CsPbBr3 nanocrystals as green phosphors, was fabricated and a white electroluminescence was achieved from this perovskite nanocrystals decorated LED.