A novel differential display material: KLuSiO: Tb/Bi phosphor with thermal response, time resolution and luminescence color for optical anti-counterfeiting.

Optical anti-counterfeiting and encryption have become a hotspot in information security. However, the advanced optical anti-counterfeiting technology still suffers from low security by single-luminescent mode. Herein, we present a novel multi-mode anti-counterfeiting strategy based on KLuSiO: Tb/Bi (KLSO: Tb/Bi) phosphors for the first time. KLSO not only provides various lattice sites for Bi ions occupying to achieve tunable luminescence but can also be non-equivalently substituted by Tb ions to produce persistent or thermo-luminescence. Furthermore, in the pattern "8888" constructed by the mixture of polyacrylic acid (PAA) with KLSO: Tb/Bi phosphors, we selectively trigger the three luminescent modes of Bi and Tb ions to realize the design of differential display in the fields of thermal response, time resolution, and luminescence color for optical anti-counterfeiting. The differentiated display can only be presented under specific multi-stimuli response, which further improves the security of information. Our work provides a new insight for designing advanced materials and can be expected to inspire future studies to explore optical anti-counterfeiting technology.