Study on the Spectral Characteristics of Orange-red Sm3+ Doped ScTaO4 Phosphor with High Thermal Stability

A series of x at% Sm3+ (x = 0.5, 1, 3, 5, 8, 10) doped ScTaO4 phosphors were prepared using a high-temperature solid-state method. The synthesized samples were structurally characterized by using X-ray diffraction (XRD) and Fourier transform infrared spectroscopy, and the diffraction data were fitted to the full spectrum. At the same time, the electronic structure (energy band and state density) and differential charge of the ScTaO4 host material were calculated. The results showed that ScTaO4 has a direct band gap with a width of 4.14 eV. The effect of Sm3+ ion doping concentrations on the emission spectrum was further explored, and the 3 at% Sm3+ ion doping concentration was selected to have the best luminescence effect. In addition, we measured the temperature-changing spectrum of the 3 at% Sm3+ doped sample in the temperature range of 300–510 K to evaluate the thermal stability of its photoluminescence spectrum. At 390 K, the emission peak intensity at 610 nm of the 3 at% Sm3+ doped sample was still 79.55% of that at room temperature, showing excellent thermal stability. At the same time, we explored the temperature quenching mechanism of the material and fitted the variable temperature spectrum to obtain the activation energy (E a) of the phosphor as 0.187 eV. The results show that Sm3+:ScTaO4 orange-red phosphor is expected to be used in the field of white LED lighting.Published by the Optical Society of Korea under the terms of the Creative Commons Attribution Non-Commercial License (https://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.