CaGa2O4:Mn2+ yellow long-lasting phosphorescent material: Preparation and anti-counterfeiting applications

With the growing severity of counterfeiting threats, counterfeiting anti-counterfeiting technologies including fluorescence, QR codes, and query-based labels, rely on static patterns with limited encryption security, leading to inadequate protection and a lack of diversity in anti-counterfeiting strength. Consequently, advancing dynamic anti-counterfeiting systems has become an urgent priority. This study developed a novel dynamic anti-counterfeiting strategy through the synthesis of yellow persistent luminescent CaGa 2 O 4 :Mn 2+ via high-temperature solid-state reaction. In this research, the results demonstrated that at the doping concentration of 0.001 mol Mn, the sample exhibited the best luminescence properties. Furthermore, electron paramagnetic resonance (EPR) and X-ray photoelectron spectroscopy (XPS) analyses revealed that electron traps responsible for the afterglow process primarily originated from oxygen vacancies, and the underlying afterglow mechanism was elucidated. Finally, CaGa 2 O 4 :Mn 2+ long-lasting phosphorescent ink was synthesized and anti-counterfeiting labels were fabricated via screen printing technology. The material's intrinsic photoresponsive behavior enables time-dependent luminance decay post-UV excitation, establishing dynamic authentication through programmable optical evolution, Which effectively realize dynamic anti-counterfeiting.