Light-emitting Sn-doped CsX (X=Cl, Br, I) materials prepared by mechanochemical processing

The success in synthesizing light-emitting lead-based halide perovskites from cesium halides (CsX, X: I, Br, and Cl) has stimulated great interests in the applications of halide perovskites and in the development of lead-free halide perovskites and related light-emitting materials. In this work, we explore the feasibility of synthesizing Sn-doped CsX powders (microcrystals) via mechanochemical processing and investigate the optical characteristics of the prepared Sn-doped CsX powders. The prepared Sn-doped CsX powders emit light with ultra-wide emission peak under UV light of 365 nm in wavelength, which is attributed to self-trapped exciton emission. The emission peak intensity decreases with the increase in temperature in the Sn-doped CsXs due to thermal quenching. The characterization of the optoelectronic response of the prepared Sn-doped CsX powders reveals that the current intensity passing through the Sn-doped CsX powders decreases with the increase of the intensity of the incident white light under the same applied voltage. Light emitting diodes are constructed from the prepared Sn-doped CsX powders and exhibit an ultra-wide spectrum spanning the range of entire visible light. The method presented in this provides a simple technique to prepare light-emitting materials of Sn-doped CsXs via mechanochemical process.