Self-activated luminescent materials have attracted increasing attention due to their broad applicability across diverse technological fields. However, a comprehensive understanding of the generation, regulation, and coexistence of self-activated luminescent centers with dopant-related emission centers remains limited. Herein, a defect-related self-activated blue-emitting center (with peak position located in the 450-500 nm range) is induced within the conventional spinel gallate phosphor system via a microwave-assisted preparation process. Notably, the self-activated emission universally coexists with the characteristic transitions of different dopant ions (Eu3+/Mn2+/Cr3+), indicating excellent compatibility between self-activated luminescent centers and multiple dopant-related emission centers. Taking ZnGa2O4:Cr3+ as an example, the self-activated luminescence shows pronounced dependence on both irradiation time and temperature. Further investigations elucidate that the electron trapping and detrapping pathways are associated with the coexisting self-activated and dopant-related luminescent centers, highlighting the distinct electron dynamics arising from their coexistence. Moreover, benefiting from the different temperature responses, a dual-emission ratiometric thermometry platform with a wide operating temperature range from 143 to 573 K is constructed. This work emphasizes the unique electron dynamics of self-activated luminescent centers and demonstrates their broad compatibility with diverse dopant systems, providing insights into the design of multifunctional luminescent materials based on intrinsic defect states.
Wang et al. (2026) studied this question.