Study on luminescence properties of Bi3+ doped Ba2YAlO5：A wide-band yellow emitting phosphor with excellent thermal stability

Abstract

The development of phosphors with excellent thermal stability remains a difficult challenge. Here, we synthesized a novel heat-quenching resistant phosphor Ba2YAlO5 doped with Bi3+ by traditional high temperature solid-state method. The crystal structure and luminescence properties of the samples were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), diffuse reflection (DR) spectra, photoluminescence (PL) spectra and so on. Under 324 nm excitation, the phosphor emits a broad-band yellow light with a peak value of 571 nm and a full width at half maximum (FWHM) of 125 nm. It is worth noting that the integrated emission intensity at 560 K is still close to that at room temperature, which can be attributed to the thermal compensation capability of the electron trap energy levels. The matrix may also have high lattice stiffness to reduce thermal quenching. In addition, Ba2YAlO5: Bi3+ exhibits yellowish white light with CIE coordinates of (0.4203, 0.4536) and a color temperature of 3669 K under excitation of a 310 UV chip. The above results indicate that Ba2YAlO5: Bi3+ is a promising yellow fluorescent powder with excellent luminescence performance for high-power devices.