Facile in-situ preparation of MAPbBr3@UiO-66 composites for information encryption and decryption

MAPbBr3 perovskite have attracted considerable attention due to their merits of high photoluminescence quantum yield and tunable photoluminescence. However, MAPbBr3 is difficult to be applied in optical information protection due to its poor stability and visibility under either ambient or UV light. Herein, the combination of PbBr2, MAPbBr3 and a Zr-based metal−organic framework (MOF) UiO-66 has been developed to prepare stable PbBr2@UiO-66 and luminescent MAPbBr3@UiO-66 composite for realizing information encryption and decryption based on the conversion of PbBr2@UiO-66 to luminescent MAPbBr3@UiO-66. Owing to the PbBr2@UiO-66 exhibits "invisible" characteristic under either ambient or UV light, information can be recorded and encrypted, which can not be read through common decryption methods. Highly luminescent MAPbBr3@UiO-66 can be quickly formed in situ by using a MABr solution that reacted with PbBr2@UiO-66, thus promoting information decryption. In addition, through water and MABr solution treatments, the luminescence of MAPbBr3@UiO-66 could be quenched and recovered for multiple information encryption and decryption.