Laser Fabrication of Multi-Dimensional Perovskite Patterns with Intelligent Anti-Counterfeiting Applications.

Perovskites have gained widespread attention across various fields such as photovoltaics, displays, and imaging. Despite their promising applications, achieving precise and high-quality patterning of perovskite films remains a challenge. In this study, femtosecond laser direct writing technology is utilized to achieve rapid and highly precise micro/nanofabrication on perovskites. The study successfully fabricates multiple structured and emission-tunable perovskite patterns composed of A 2 (FA) n-1 Pb n X 3n+1 (A represents a series of long-chain amine cations, and X = Cl, Br, I), encompassing 2D, quasi-2D, and 3D structures. The study delves into the intricate interplay between fabrication technology and the growth of multi-dimensional perovskites: higher repetition rates, coupled with appropriate laser power, prove more conducive to perovskite growth. By employing precise halogen element design, the simultaneous generation of two distinct color quick-response (QR) code patterns is achieved through one-step laser processing. These mirrored QR codes offer a novel approach to anti-counterfeiting. To further enhance anti-counterfeiting capabilities, artificial intelligence (AI)-based methods are introduced for recognizing patterned perovskite anti-counterfeiting labels. The combination of deep learning algorithms and a non-deterministic manufacturing process provides a convenient means of identification and creates unclonable features. This integration of materials science, laser fabrication, and AI offers innovative solutions for the future of security features.