Achieving mechano-upconversion-downshifting-afterglow multimodal luminescence in Pr3+/Er3+ coactivated Ba2Ga2GeO7 for multidimensional anticounterfeiting

Abstract

Luminescent materials play a vital role in information encryption and anti-counterfeiting applications due to their excellent optical performance. Unfortunately, many reported luminescent materials are based on a fixed excitation mode and mono-color output, resulting in a poor anti-counterfeiting effect. Therefore, it is still a challenging task to develop multimodal anti-counterfeiting materials with adjustable color, variable excitation patterns and multitemporal features, especially in a single matrix. In this work, a highly integrated multimodal Ba₂Ga₂GeO₇:0.04Pr³⁺,0.08Er³⁺ material is reported, which can show color-tunable Downshifting Luminescence (DSL) (white and green), white Persistent Luminescence (PersL), green Upconversion Luminescence (UCL) and white Mechanoluminescence (ML). Based on these integrated performances, the as-obtained multimodal Ba₂Ga₂GeO₇:0.04Pr³⁺,0.08Er³⁺ material is fabricated into an anticounterfeiting device, which can realize synchronous multidimensional information encryptions and anticounterfeiting using common tools (ultraviolet (UV) light, near-infrared (NIR) light and pen writing). The results indicate that these integrated features will be difficult to fake and show high-level security in the field of advanced anticounterfeiting.