Mechanism for tunable broadband white photoluminescence of one-dimensional (C4N2H14)2Pb1-xMnxBr4 perovskite microcrystals

This work demonstrated that tunable photoluminescence of the low-dimensional hybrid halide perovskites via the doping strategy is feasible, and hence paves the way towards the investigation and application of high-performance single photoluminescence perovskite material with broadband white light emission. This work reported the first synthesis of one-dimensional (1D) (C4N2H14)2Pb1-xMnxBr4 perovskite microcrystals (MCs) with tunable broadband white-light emission and long-lived STE (self-trapped exciton) emission. The overall photoluminescence mechanism under the regulation of defect engineering of 1D (C4N2H14)2Pb1-xMnxBr4 MCs was formulated for the first time. Photoluminescence mechanism of these MCs involves competition of FE (free exciton) and STE and 4T1 states. This competitive mechanism further promotes photoluminescence tunability ranging from blue-white to white to orange-red for Mn-doped MCs. Moreover, time-resolved emission spectra show the changes of lifetime of these MCs at different emission wavelength. These perovskite MCs have a long-lived STE emission, which indicates that the more effective exciton combinations are occurring in them. For comparation, the Mn-doping strategy can regulate structural defect of these MCs, which promotes or suppresses transitions of FE→STE, FE→4T1, STE→FE and further tunes photoluminescence. This work paves the way towards the investigation and development of optoelectronic application of perovskite MCs material.