Carbon dots embedded in lead-free luminescent metal halide crystals toward single-component white emitters

The development of single-component white emitters for white light-emitting diodes (WLEDs) remains challenging. Herein, a rare earth-free white light-emitting composite is developed by assembling blue-emitting carbon dots (CDs) and yellow-emitting Cs2InCl5 center dot H2O:Sb3+ metal halide crystals via a facile liquid-liquid diffusion-assisted crystallization approach. The encapsulation mechanism is then analyzed. Depending on the ratios of blue/yellow emitters, these luminescent composites exhibit white light emission with tunable cold and warm hues. The composites also possess prominent ultraviolet resistance, thermal tolerance, and good stability at about 200 degrees C. By employing such CDs in metal halide composites as a converter, a WLED is successfully fabricated with a high color rendering index of 93.6, benefiting from the assembled blue and yellow broadband emission. With this strategy, the developed composites show great promise in next-generation WLED lighting.

Automated summary

In this study, a rare earth-free white light-emitting composite was developed by assembling blue-emitting carbon dots and yellow-emitting metal halide crystals. The composites exhibited tunable white light emission with high color rendering index and showed excellent ultraviolet resistance and thermal stability. The findings demonstrate the great potential of these composites in next-generation WLED lighting.