Erasable glass-stabilized perovskite quantum dots for NIR-laser-stimuli-responsive optical security

Stimuli-responsive smart luminescent materials capable of dynamic color emission with distinct spectral profile/intensity are highly desirable for anti-counterfeiting applications. Here, we report the dynamic manipulation of photoluminescence from metal halide CsPbX3 (X = Br, I) perovskite quantum dots (PeQDs) inside a glass medium by tuning local temperature fields in real time in combination with the efficient photothermal material CsYb2F7@glass. Benefiting from the effective protection of the inorganic glass matrix and low exciton binding energy of PeQDs, it is feasible to realize stable and reversible ON/OFF full-spectral emissions of PeQDs upon commercial 980 nm laser stimulation. The dynamic combination of downshifting PeQDs and upconverting lanthanide-doped CsYb2F7 can be elaborately designed to produce a series of erasable photochromic anti-counterfeiting patterns and multi-dimensional optical encodings.