CsPbBr3 nanocrystals embedded glass enables highly stable and efficient light-emitting diodes

All inorganic cesium lead halide perovskite nanocrystals have great potential for electrically pumped or optically pumped light emitting diodes. External quantum efficiency of electrically pumped perovskite nanocrystals-based light emitting diodes are strongly affected by the imbalanced charge injection, electric field induced ion diffusion and joule heating. External quantum efficiency of optically pumped perovskite nanocrystals-based light emitting diodes are also affected by their photo-stability and photoluminescence quantum efficiency. Here, highly efficient light-emitting diodes are realized by employing CsPbBr3 nanocrystals embedded glasses as color converter. It is found that increase in molar ratio between bromine and lead in glasses results in the passivation of bromine vacancies of CsPbBr3 nanocrystals, and significantly improves photoluminescence quantum efficiency and photo-stability of CsPbBr3 nanocrystals embedded glasses. With these CsPbBr3 nanocrystals embedded glasses as color converter, highly efficient green light-emitting diodes with external quantum efficiency of 33.72% and white light-emitting diodes with external quantum efficiency of 43.27% are realized. These results demonstrate that cesium lead halide perovskite nanocrystals embedded glasses are promising for optically pumped light-emitting diodes.