Enhanced blue emission of BaGaO: Bi phosphor co-doped with alkali metal ions.

A novel Bi doped BaGaO phosphor was successfully synthesized by high-temperature solid-state method in this work. The results of X-ray diffraction (XRD) characterization, scanning electron microscope (SEM) characterization and energy dispersive spectrometer (EDS) characterization indicate that Bi ions were doped successfully into the lattice The phosphor has a broad emission band covering the 350-580 nm spectral region peaked at 416 nm under the excitation at 340 nm, due to the P → S transition of Bi ions. Furthermore, when Na ions and K ions were co-doped, the emission intensity increased by 1.53 times and 1.55 times, respectively. By combining BaGaO: Bi, K, the commercial green phosphor (Ba, Sr)SiO: Eu and the commercial red phosphor CaAlSiN: Eu with a 340 nm UV chip, a pc-white LED was fabricated successfully. And the chromaticity coordinates of the WLED is (0.3647, 0.3329), the value of Correlated Color Temperature (CCT) is 4136 K and the Color Rendering Index (CRI) = 88.4. All results indicate that BaGaO: Bi phosphor can make a great contribution to the field of NUV-based WLEDs.