Pb2+/Mn2+ co-doped Cs2ZnBr4 microcrystals with dual-band tunable white light emission

The photoelectric properties of lead halide perovskite have been extensively investigated. However, its application in the field is greatly limited due to its poor instability and high lead content. With the aim of addressing these problems, in this study, Cs2ZnBr4:Pb2+/Mn2+ microcrystals were initially synthesized using a simple precipitation method. By manipulating the lead concentration, the emission ranging from cyan to green could be adjusted in Cs2ZnBr4:Pb2+. Co-doped Cs2ZnBr4:Pb2+/Mn2+ microcrystals with the precise regulation of the doping concentration of Pb2+ and Mn2+ were obtained through precipitation. The dual-mode emission of cyan and orange-red is successfully obtained. It is important that single white light emission is achieved in Cs2ZnBr4:Pb2+/Mn2+ microcrystals, exhibiting tunability from cold white to warm white. Moreover, Cs2ZnBr4:Pb2+/Mn2+ microcrystals are demonstrated remarkable air stability: it retains 86.27 % of the initial fluorescence intensity after 45 days in ambient conditions; it exhibits excellent UV stability, with 88.3 % of the initial fluorescence intensity maintained even after nearly 30 h of ultraviolet irradiation. Therefore, this research is anticipated to have broad applications not only in the field of solid-state lighting as UV-excited white LEDs but also in serving as a valuable reference for the exploration of low-lead halide luminescent materials.