Tunable cold/warm white light emission from Bi3+/Te4+ co-doped Cs2ZrCl6 perovskite phosphors

Combining a single-component white-light phosphor with ultraviolet light emitting diode chips emerges as a promising method to produce white-light-emitting diodes (WLEDs). Nevertheless, it is still a challenge for synthesizing single-component white-light phosphors with a high color rendering index (CRI). Herein, Bi3+/Te4+ co-doped Cs2ZrCl6 perovskite white-light phosphor is presented with a high CRI of 91.7 and good stability against oxygen, water, and heat. The Cs2ZrCl6 microcrystals were prepared using an ultrasound-assisted hydrochloric acid method with controllable Bi3+ and Te4+ dopant contents. By manipulating the excitation wavelength, the emission light can be altered between cold and warm white. The Bi3+/Te4+ co-doped Cs2ZrCl6 phosphor can also emit the warm-white light, showing a high photoluminescence quantum yield of 82.9%. The presented Bi3+/Te4+ co-doped Cs2ZrCl6 perovskite phosphors with a high CRI and great environmental stability offer a new approach for the synthesis of single-phase white-light phosphors and have high potentiality for the application of WLEDs.