Luminescent properties and performance tune of novel red-emitting phosphor CaInBO4: Eu3+

Abstract

Novel CaInBO4: xEu3+ phosphors were synthesized by solid–state reaction method. Their luminescent properties were characterized mainly by UV–visible PLE, PL, VUV, Decay lifetime, and TG-DTA. The excitation and emission spectra indicate that these phosphors can be effectively excited by ultraviolet about ～254 nm and exhibit red emission centered at ～613 nm attributed to 5D0→7F2 transition of Eu3+. Optimum Eu3+ concentration of this phosphor is around 9 mol%. The effect of Al3+/Gd3+ and Ba2+/Sr2+ co-doped CaInBO4: Eu phosphor have been investigated, and the concentration dependence of the emission intensity shows that the optimum doping concentrations of Al3+ and Ba2+ are 3 mol% and 6 mol%, respectively. The UV–vis diffuse reflectance spectra indicate that these phosphors have wide transparent region and the incorporation of Al3+ ions and Ba2+ ions is in favor of light absorption for CIBO: Eu phosphor. The band gaps for these samples were obtained from diffuse reflection spectra, and the excitation wavelengths of phosphors were modified by adjusting their band gaps. According to their decay curves, the calculated lifetime of (Ca1−z, Ba/Srz) (In1−x−y, Al/Gdy) BO4: xEu3+ phosphors are all shorter than 2 ms. The chromaticity diagram shows that these phosphors can emit red light. The TG-DTA data presents that these phosphors have good thermal stability below 1100 °C. The present work suggests that these novel phosphors have potential applications for fluorescent lamps.