Multicolor lu-minescence of Cs2KLuCl6 for an-ti-counterfeiting and information encryption ap-plications

Abstract

Sb3+ doped inorganic perov-skites have attracted great attention for anti-counterfeiting and infor-mation encryption applica-tions due to their excellent optical properties. We have synthesized a novel perov-skite Cs2KLuCl6, which ex-hibits weak cyan emission originating from the self-trapped excitons (STEs) of the host. Its photolumines-cence quantum yield is enhanced from 2% to 68% by Sb3+ doping. The energy transfer channel from STEs to Ho3+ was constructed, and the luminescence color was modulated from cyan to white with the increase of Ho3+ doping concentra-tion. The Sb3+/Ho3+ co-doped sample has two-color luminescence performance due to the introduction of new emission centers. Up-conversion green emission was obtained by introduc-ing Yb3+/Er3+. Finally, the optical properties of the obtained samples were utilized to design an anti-counterfeit label and in-formation encryption strategy.