Three-step fine-tuning by doping Bi3+, Tb3+ and Eu3+/Sm3+ in Gd2MoB2O9 host for accurate white emission

Abstract

Tuning for accurate white light emission in single-composition phosphor is challenging due to the presence of complex energy transfer. Herein we report the synthesis and characterization of single-composition white light emission phosphors with accurate color coordinates, which were tuned through a three-step doping strategy. Under the excitation of 280 ​nm UV light, Gd1.474MoB2O9: 0.30Bi3+, 0.20Tb3+, 0.026Eu3+ and Gd1.46MoB2O9: 0.30Bi3+, 0.19Tb3+, 0.05Sm3+ exhibit white light emission with color coordinates of (0.339, 0.335) and (0.332, 0.346), very close to standard white light. The emission intensity at 100 ​°C maintains 82.07% and 91.35% of that of room temperature, demonstrating good thermal stability. The Gd1.474MoB2O9: 0.30Bi3+, 0.20Tb3+, 0.026Eu3+ and Gd1.46MoB2O9: 0.30Bi3+, 0.19Tb3+, 0.05Sm3+ white phosphors have the advantages of convenient synthesis conditions, stable chemical properties and emission very close to standard white light. This three-step doping strategy can be used for designing Bi3+ based single-composition white emission phosphors.