Multi-color upconversion luminescence of Er3+ under the cooperative regulation of Yb3+ and Ce3+ for optical anti-counterfeiting

The most effective approach to regulating the color of upconversion luminescence is through doping with lanthanide ions that possess the ability to regulate energy processes, which holds significant importance for the application of upconversion luminescent materials in the domains of optical data storage and anti-counterfeiting technology. In this work, a multi-component upconversion luminescent material NaYF 4 : Er 3+ , Yb 3+ , Ce 3+ with near-infrared response and Er 3+ doping ranging was prepared by low-temperature combustion synthesis. Due to the unique 4f 13 electronic configuration of Yb 3+ , the probability of Er 3+ falling into the trap energy level increases, thereby reducing the emission of Yb 3+ . The emission color of Er 3+ can be altered by doping with Ce 3+ , which is different from the enhancement of red emission by Ce 3+ in other studies. In addition, the different luminescent properties of the samples under different wavelengths of excitation were studied, and a fluorescence security mode was designed to demonstrate its potential application value in anti-counterfeiting and hiding important information. This research offers new insights into the mechanisms underlying the upconversion phenomenon in Er 3+ through multi-ion doping, and provides new approaches for the design of photochromic upconversion phosphors.