A novel red BaLaInO4: Eu3+ phosphor for WLEDs

The synthesis of BaLaInO4: xEu(3+) (x = 0, 0.05, 0.1, 0.2, 0.3, 0.4, and 0.5) phosphors using a high-temperature solid-state method was firstly successfully accomplished. The obtained samples were characterized using X-ray powder diffraction, scanning electron microscopy, and photoluminescence spectrum to analyze their phase composition, morphology, and luminescence properties. Meanwhile, the bandgap and density of states were studied through first principles computation. The results of the photoluminescence spectrum of the samples display that they can be successfully excited by both ultraviolet and blue light. However, concentration quenching occurred when x > 0.3. The thermal stability, color purity, color coordinates, and correlated color temperature of BaLaInO4: xEu(3+) were also extensively studied. The I-423K/I-298K value of BaLaInO4: 0.30Eu(3+) was 61%, and the color purity of BaLaInO4: 0.30Eu(3+) phosphor was 100%. In addition, the BaLaInO4: 0.30Eu(3+) sample was mixed with commercial blue and green phosphors in a certain proportion to make WLEDs. The color coordinates of fabricated WLED were (0.3285, 0.3855), the CRI was 93.1, and the R9 value was 69. Therefore, BaLaInO4: xEu(3+) phosphors are considered to be promising luminescent materials for WLEDs.