Aqueous-triggered self-destructive persistent luminescent nanoparticles for dynamic hierarchical security encoding

Abstract

Persistent luminescence has emerged as a robust platform for anti-counterfeiting applications due to its exceptional spatial-temporal decoding capability. Yet, conventional strategies often suffer from uniform emission patterns and predictable replication, compromising their security. Herein, we present “Snap-PLNPs”—near-infrared emitting CaS:Tm persistent luminescent nanoparticles engineered to undergo aqueous-triggered self-destruction via a hydrolysis mechanism. In contrast to traditional photophysical approaches, this chemically initiated degradation irreversibly terminates the luminescence, ensuring that security information can be decoded only once. Moreover, by incorporating an additional SiO₂ shell, we introduce a programmable delay in the hydrolysis process, thereby modulating the duration of the emission and adding a temporal regulation layer. This dual control—combining instantaneous chemical deactivation with time-resolved modulation—establishes a dynamic hierarchical security encoding framework. When embedded into laser-engraved logos, these CaS:Tm@SiO₂ hybrids enable a novel triple-layer anti-counterfeiting strategy that integrates spatial, temporal, and chemical dimensions. Our results underscore the potential of Snap-PLNPs as a next-generation platform for robust and adaptive security technologies.