Preparation and optical properties of a novel double-perovskite phosphor, Ba2GdNbO6:Mn4+, for light-emitting diodes

Red phosphors serve an important function as red components of warm white light-emitting diodes (WLEDs). Given their remarkable luminescent properties and low cost, Mn4+-doped phosphors are attracting significant attention. In this study, the novel red phosphor Ba2GdNbO6:Mn4+ was synthesized through high-temperature solid-state reaction. The host Ba2GdNbO6 with a double-perovskite structure was investigated. Scanning electron microscopy and thermogravimetric analysis were performed to evaluate the structure and thermal stability of the phosphor, respectively. PLE and photoluminescence spectra were further used to study the luminescence properties of the phosphor. Moreover, crystal field strength and Racah parameters were calculated to estimate the nephelauxetic effect of Mn4+ on the Ba2GdNbO6 host lattice. Thermal quenching characteristics were also analyzed. The fabricated red-emitting LED revealed its potential application in WLEDs.