High-brightness Sm³⁺-doped La_0.67Mg_0.5W_0.5O₃ red phosphor for NUV light-emitting diodes application

Red phosphors La_0.67(1−x)Mg_0.5W_0.5O₃:xSm³⁺ (x = 0.01, 0.02 0.03, 0.04, 0.05, 0.06, and 0.07) were synthesized by a conventional solid-state reaction (SSR) route. The X-ray diffraction (XRD) patterns, photoluminescence spectra, ultraviolet–visible reflection spectroscopy, decay time and the International Commission on Illumination (CIE) chromaticity coordinates of these compounds were characterized and analyzed. The emission spectra of the La_0.67(1−x)Mg_0.5W_0.5O₃:xSm³⁺ phosphors consisted of some sharp emission peaks of Sm³⁺ ions centered at 563 nm, 601 nm, 646 nm. The strongest one is located at 646 nm due to ⁴G_5/2–⁶H_9/2 transition of Sm³⁺, generating bright red light. The optimum dopant concentration of Sm³⁺ ions in La_0.67(1−x)Mg_0.5W_0.5O₃:xSm³⁺ is 2 mol%. The CIE chromaticity coordinates of the La_0.67(1−x)Mg_0.5W_0.5O₃:xSm³⁺ phosphors were located in the red region. The La_0.67(1−x)Mg_0.5W_0.5O₃:xSm³⁺ phosphors may be potentially used as red phosphors for white light-emitting diodes. - Highlights: • The novel La_0.67Mg_0.5W_0.5O₃:Sm³⁺ red phosphor was synthesized. • Photoluminescence (PL) properties of La_0.67Mg_0.5W_0.5O₃:Sm³⁺ phosphor also discussed. • La_0.67Mg_0.5W_0.5O₃:Sm³⁺ could be a potential red phosphor for NUV LEDs.