Fig. 6From: Eu2+-Activated Green-Emitting Phosphor Obtained from Eu3+ Ions doping Zeolite-3A in Air Surroundings and Its Efficient Green Light-Emitting Diodesa Electroluminescence emission spectrum at 3 V voltage for zeolite-3A: 1.3 wt% Eu phosphor sintered at 1400 °C for 3 h, and the inset is a photograph of working green LED at 3 V voltage. b Color coordinate in the CIE1931 diagramBack to article page