Ambient-stable Mg-doped CsCuI nanocrystals with enhanced photoluminescence for color conversion blue LEDs.

We successfully synthesized Mg-doped CsCuI nanocrystals (NCs) under ambient conditions. The 10% Mg-doped CsCuI NCs exhibit significantly enhanced optical properties, achieving a photoluminescence quantum yield (PLQY) of 25.80% and a narrow emission full width at half maximum (FWHM) of 78 nm. The 10% Mg-doped NCs also exhibited improved thermal and water stability, retaining 67% of their initial photoluminescence (PL) intensity when heated from 25°C to 100°C and maintaining blue light emission after 30 min in aqueous environments. When integrated into a color conversion LED, these NCs achieved simultaneous improvements in emission characteristics, showing a narrowed FWHM (81 nm) and higher emission efficiency compared to undoped counterparts.