Fluorescence properties and thermal stability of Sr2Gd1-xNbO6: xEu3+ with dual-wavelength excitation response

A series of double perovskite-type Sr2Gd1-xNbO6: xEu3+ (x = 0.04–0.12) red-emitting phosphors were successfully synthesized by a solid-state high-temperature sintering reaction, and the microstructure and luminescent performance of the phosphor are investigated in detail. The red-emitting phosphor has a monoclinic crystal structure with a space group of P21/c. The optimal concentration of the Eu3+ dopant in the Sr2GdNbO6 host was 0.08. Under dual-wavelength excitation of λex = 468 nm and λex = 395 nm, phosphor emits a red-orange color, and the principal emission peaks are located at 622 nm and 593 nm, which correspond to the 5D0→7F2 and 5D0→7F1 energy level transitions of Eu3+, respectively. Under the excitation of blue light λex = 468 nm, the phosphor exhibits not only a greater thermal stability but also a high luminescence color purity (93%). It is a new potentially red-emitting phosphor with dual wavelength excitation responsiveness.