Sr2MgWO6:Ni2+-A highly efficient and tunable photoluminescence near-infrared phosphor for NIR-II light source applications

The rapid development of near-infrared (NIR) phosphorescent conversion light-emitting diodes (pc-LED) in imaging and detection indicates a strong demand for NIR-II region luminescent materials. Unfortunately, the lack of effective IR-II phosphors that can be excited by commercial blue LED chips has hindered the application of NIR spectroscopy. In this paper, we introduce a novel ultra-broadband NIR phosphor Sr2MgWO6:Ni2+ characterized by an emission peak at 1400 nm with a full width at half maximum (FWHM) of 237 nm. A tunable NIR emission from 1400 to 1485 nm is achieved by cation co-substitution of Ca2+ for Sr2+, and the corresponding FWHM can be modified from 237 to 292 nm. NIR-II pc-LEDs was fabricated by combining prepared near-infrared phosphors with blue LED chips to visually demonstrate their potential applications in authentication artistic works such as oil paintings. These results not only have theoretical significance for further understanding of the structure-property relationship of NIR-II luminescent materials, but also have reference value for developing more practical materials.