Crystal structure and optical properties of white light-emitting Y2WO6:Sm3+ phosphor with excellent color rendering

A new single-phased white light-emitting phosphor, Y2WO6:Sm3+, was synthesized via conventional solid-state reaction calcining in air. The Y2WO6:Sm3+ samples were characterized using powder X-ray diffraction and refined with Rietveld methods. The phosphors exhibit a green emission from the host as well as a red emission from the dopant under ultraviolet excitation (300-380 nm). The color coordinates can be gradually tuned from green (0.247, 0.380) through white-light (0.319, 0.382) toward orange (0.335, 0.390) in the visible spectral region by systematically changing the Sm3+ dopant concentration. In addition, combining a 365 nm near-ultraviolet chip and Y2WO6:0.02Sm(3+) phosphor produced a white light-emitting diode, which exhibited an excellent color rendering index (Ra) of 92.3, a correlated color temperature of 5916 K and CIE coordinates of x = 0.3246, y = 0.3242.