Occlusal splint with mechanoluminescence properties based on BaSi2O2N2:Eu2+ cyan phosphor prepared by deposition-precipitation method

A series of Eu2+ activated BaSi2O2N2 oxynitride cyan phosphors with high crystallinity have been successfully synthesized by a facile deposition-precipitation (DP) method. Under excitation of 375 nm, the photoluminescence emission intensity at 495 nm was enhanced by 157% for BaSi2O2N2:Eu2+ prepared by DP method compared to the sample prepared by traditional solid-state reaction (SSR) method due to the uniform distribution of Eu2+ ions. Accordingly, BaSi2O2N2:0.02Eu2+ phosphor prepared by DP method exhibits a longer fluorescence lifetime (553.6 ns) than that (472.8 ns) prepared by SSR method. Interestingly, Eu2+ ions can incorporate in BaSi2O2N2 lattices through DP process even at a lower temperature (1000 °C) compared to the conventional temperature (1450 °C) during SSR process. Finally, the flexible occlusal splints based on BSON:Eu2+/PDMS composite elastomers has been fabricated by the excellent mechanoluminescent (ML) property of BaSi2O2N2:Eu2+ phosphors. The ML signal of BSON:Eu2+/PDMS occlusal splints under mechanical stimulation allows visualization of force magnitude during occlusal examination for the treatment of clinical oral disorders such as temporomandibular disorders.