Dual color luminescence of Mn2+ doped lead-free Cs3Cu2I5 perovskite phosphors and their LED solid-state lighting and anti-counterfeiting applications

Cs3Cu2I5 have recently attracted far-flung and fervency interests with the characters of low cost, high photoluminescence quantum yield, green and non-toxicity. In addition, continuous tuning of the luminescence properties could be realized in Cs3Cu2I5, which would benefit its optical applications. Herein, Mn2+ is chosen as the luminescent center into Cs3Cu2I5 through solid-state ball milling method. Its structure and photoluminescence properties have been studied by various characterization methods such as X-ray powder diffractions, fluorescence spectroscopy, and element mapping. These results showed that Mn2+ doping into Cs3Cu2I5 makes little change on the crystal structure of Cs3Cu2I5. The copper ions and manganese ions exist stably in the form of Cu+ and Mn2+, respectively. After Mn2+ doping, a new emission peak appears at 560 nm except for the intrinsic blue emission of Cs3Cu2I5, thus realizing dual color luminescence. This material also exhibits excellent thermal stability, making it suitable for solid-state lighting and anti-counterfeiting applications.