Controllable decomposition/recrystallization of water-sensitive CsPbBr3 glass ceramics for dynamic anti‐counterfeiting with high security

Due to the sensitivity to water, the all-inorganic CsPbBr3 nanocrystals have been widely applied in information encryption with spatial dimensions. However, the absence of time-dimension information limits the information capacity for the application of CsPbBr3. In this work, the CsPbBr3 nanocrystal was combined with water-sensitive borophosphate glass, achieving decomposing/recrystallization of CsPbBr3 nanocrystal with multi-dimension. The addition of SiO2 confirms that the collapse of the borophosphate glass network structure causes the exposure of the CsPbBr3 nanocrystals. The decomposition and recrystallization mechanism of CsPbBr3 nanocrystals in glass-ceramics upon encountering water has been verified. Finally, an information encryption strategy, using the mixture of CsPbBr3 glass ceramic and sodium carboxymethylcellulose as ink, is designed via adopting screen-printing technology, which not only provides a new idea for the preparation of CsPbBr3 nanocrystals, but also establish a new avenue for the information encryption technology.