A novel trap-controlled mechanoluminescent material of SrGa4O7:Tb3+ for advanced anti-counterfeiting

Mechanoluminescent (ML) materials, which emit light by utilizing mechanical energy, have significant application prospects in fields of stress sensing, flexible electronics, and anti-counterfeiting. Current research in ML materials has largely focused on optimizing the performance of known ML materials, whereas the exploration of novel ML materials continues to be a pressing priority. Here, a novel grossite-type SrGa 4 O 7 :Tb 3+ ML material was successfully synthesized via a high-temperature solid-state method. Under mechanical stimulation, this material exhibits bright green ML emission, with a positive correlation between luminescence intensity and applied stress. The photoluminescence (PL), thermoluminescence (TL), and temperature-dependent ML spectra indicate that the ML emission in SrGa 4 O 7 :Tb 3+ originates from the defect-regulated mechano-optical conversion mechanism. Furthermore, a signature verification device based on SrGa 4 O 7 :Tb 3+ was also successfully fabricated, demonstrating its potential for advanced anti-counterfeiting. This work not only deepens our understanding into the development of new ML materials but also provides a promising platform for applications in anti-counterfeiting.