High-brightness red-emitting double-perovskite phosphor Sr2LaTaO6:Eu3+ with high color purity and thermal stability [Invited]

Bright Eu3+-activated double-perovskite Sr2LaTaO6 red-emitting phosphors were successfully synthesized by a high-temperature solid-state method. Under near-ultraviolet excitation at 394 nm, optimal Sr2LaTaO6:0.2Eu3+ phosphors emitted high-brightness red light around 613 nm with the International Commission on Illumination chromaticity coordinates (0.650, 0.349). Notably, the color purity can reach 92%. Impressively, the favorable thermal stability of the Sr2LaTaO6:0.2Eu3+ phosphors was characterized by temperature-dependent emission spectra at different temperatures from 303 to 463 K, and the emission intensity at 423 K remained 73% of its value at 303 K. All of the results suggested that the as-prepared Sr2LaTaO6:0.2Eu3+ phosphors can be used in near-ultraviolet-excitable white light-emitting diodes as a red-emitting color converter.