Excitation-Dependent Emission in All-Inorganic Lead-Free Cs2ScCl5•H2O Perovskite Crystals

Low-dimensional lead-free metal halides have recently attracted a great deal of attention for their unique photoluminescence properties. In this work, a new all-inorganic zero-dimensional (0D) rare-earth perovskite, namely Cs2ScCl5 center dot H2O is reported. The 0D crystal exhibits a rare phenomenon of excitation-wavelength dependent emission from blue-green to white to yellow at room temperature. Spectroscopic characterizations indicate the tunable emission is originated from two distinct self-trapped exciton states. In addition, the yellow emission quantum yield can be enhanced from 1.2% to approximate to 100% by doping Sb3+ ions into the crystal. The work not only presents a new all-inorganic semiconductor with tunable emission colors, but also provides a design strategy for developing nontoxic and high-performance light-emitting materials.

Automated summary

This work reports a new all-inorganic zero-dimensional rare-earth perovskite material that exhibits tunable emission colors from blue-green to white to yellow at room temperature by controlling the excitation wavelength, and enhances the quantum yield of yellow emission by doping Sb3+ ions. The study not only presents a new type of light-emitting material, but also provides a strategy for the design of non-toxic and high-performance light-emitting materials.