One Step In Situ Confinement Synthesis of White CDs@ZIF‐8 Phosphors with High Photoluminescence Thermally Stable for Laser Diode

Abstract Carbon dots (CDs), as an emerging fluorescent material, have been successfully employed in white laser diode (WLD). However, it is still a challenge to realize single‐component white CDs‐based phosphors with high photoluminescence thermal stability for WLD. Here, one‐step synthesis of white CDs@ZIF‐8 (W‐CDs@ZIF‐8) phosphors with high photoluminescence thermal stability is achieved through in situ heat treatment of ZIF‐8 encapsulated with carbon source. Benefiting from the resonance energy transfer of CDs generated inside ZIF‐8, W‐CDs@ZIF‐8 exhibits an ultra‐wide full‐spectrum emission ranging from 400 to 750 nm. Because of the removal of unstable functional groups and the formation of the rigid structure of ZIF‐8 by heat treatment at 280 °C, W‐CDs@ZIF‐8 remains unchanged in fluorescence under LD irradiation for 60 min and at 205 °C, as well as the initial decomposition temperature is as high as 542 °C. The WLD device fabricated from W‐CDs@ZIF‐8 as phosphor exhibits a color coordinate of (0.29, 0.32), a color rendering index of 83, a correlated color temperature of 8154 K, and satisfactory stability. This work provides a new route for the development of CDs‐based phosphors with high photoluminescence thermal stability and is of great significance for promoting the development of CDs in solid‐state lighting.