Effects of different dopants and synthesizing temperatures on the microstructures and photoluminescence properties of Sr1.4Ba0.6SiO4-based phosphors

Abstract

Rare-earth ions can be used to design a virtually unlimited number of new luminescent materials because of their special energy level transitions in different energy bands. In this study, Nd2O3, Eu2O3 and Sm2O3 were used as dopants to produce commercial Sr1.4Ba0.6SiO4:Nd, Sr1.4Ba0.6SiO4:Eu, and Sr1.4Ba0.6SiO4:Sm phosphors by a solid-state reaction method. All the Sr1.4Ba0.6SiO4-based phosphors were synthesized in the temperature range of 1000–1300 °C for 2 h. XRD patterns revealed that when different dopants and synthesizing temperatures were used, the Sr1.4Ba0.6SiO4-based phosphors had different physical and luminescent properties. The SiO2 phase in Sr1.4Ba0.6SiO4:Nd powder was observed when the synthesizing temperature was 1000 °C but was absent if the synthesizing temperature was higher. There were no raw material or secondary phase residuals in the Sr1.4Ba0.6SiO4:Eu powder, even when the synthesizing temperature was 1000 °C. In the case of Sr1.4Ba0.6SiO4:Sm powder, secondary or unknown phases were still observed if the synthesizing temperature was lower than 1300 °C. When the temperature was increased from 1000 to 1300 °C, the 2θ value and the full width at half maximum value of the (103) plane underwent no apparent change in the Sr1.4Ba0.6SiO4:Nd and Sr1.4Ba0.6SiO4:Eu powders. This study also thoroughly investigated the effects of different dopants and synthesizing temperatures on the luminescent properties of Sr1.4Ba0.6SiO4-based phosphors.