Triboelectrification-induced mechanoluminescence of isomorphic Sr3MO4F:Ln (M = Al, Ga): Performance and difference

The development of self-powered and non-pre-irradiation mechanoluminescent (ML) materials holds significant promise for achieving dynamic and real-time visualized stress distribution display. In this work, isomorphic ML materials Sr 3 MO 4 F:Ln 3+ (M = Al, Ga) were synthesized that exhibit repeatable ML without the need for pre-irradiation. These materials present non-piezoelectric and non-trap-controlled ML behaviors, resulting from contact electrification due to the interaction between phosphor and polydimethylsiloxane polymer under stress. Given the similar crystal structures and spectral properties, we substitute the complex measurements of electron transfer in the contact electrification process with straightforward theoretical modeling and calculations to elucidate the origins, mechanisms, and processes of interfacial triboelectrification-induced ML behaviors between Sr 3 MO 4 F phosphors and PDMS polymers. The experiments and density functional theory (DFT) calculations indicate a positive correlation among transferred charge, surface triboelectric potential, and ML intensity. This work not only introduces a new class of ML materials but also makes an effort at establishing and harmonizing the structure-performance relationships for triboelectrification-induced ML materials.