Synthesis and luminescent properties of low oxygen contained Eu2+-doped Ca-α-SiAlON phosphor from calcium cyanamide reduction

A new convenient calcium cyanamide (CaCN2) reduction route was developed to synthesize the Eu2+ activated Ca-α-SiAlON phosphors containing low oxygen content. The luminescence properties of the obtained products were investigated for white LEDs application. The critical Eu2+ concentration in various hosts and its effect on the photoluminescence properties were studied. The optimized sample (10at.% Eu2+vs. Ca2+) could be efficiently excited by the current GaN/InGaN blue LED chips and provided emission intensity competitive with that of YAG:Ce3+ (P46-Y3) standard, revealing that this phosphor was a potential candidate for phosphor-converted white LEDs.