Variable halide perovskites: diversification of anti-counterfeiting applications

Various anti-counterfeiting techniques have wide applications in logistics, aviation, documentation and military. Achieving facile, quick, low-cost, and difficult-to-replicate advanced luminescence anti-counterfeiting plays a crucial role in preventing and deterring the acts of counterfeiting. Halide perovskites (HPs) possess excellent optoelectronic characteristics and structural versatilities, offering great potential in multimodal and multicolor anti-counterfeiting. This review emphasizes the effects of dimensionality, the coordination number, and bond length in HPs on the regulation mechanism of photoluminescence. Through ion doping and external stimuli of HPs, their optical characteristics and crystalline structures can be changed. Furthermore, HPs have attractive application potential due to their sensitivity to controllable light, thermo, solvent, mechano, and other conditions. The unique structure makes HPs exhibit an afterglow phenomenon, providing promising technical support for anti-counterfeiting work and high-level encryption/decryption. Finally, we present future prospects on the development of HPs which include production processes and potential high-end anti-counterfeiting strategies. This review emphasizes how the dimensionality, coordination number and bond length of halide perovskites (HPs) regulate their photoluminescence. HPs have good application potential due to their sensitivity to light, solvent, heat etc., facilitating anti-counterfeiting and encryption/decryption.