Red phosphor Ca2Ge7O16:Eu3+ for potential application in field emission displays and white light-emitting diodes

A novel red emitting phosphor of Eu3+ doped Ca2Ge7O16 was prepared through the solid state reaction. The luminescence properties were studied in detail by photoluminescence excitation (PLE), emission (PL) spectra and cathodoluminescence (CL). Under the excitation of ultraviolet light, Ca2Ge7O16:Eu3+ phosphor shows the characteristic D-5(0)-F-7(J)(J= 1, 2, 3, 4) transition of Eu3+ with two different emissions due to the two kinds of Eu3+ ions. The luminescent intensity could be improved by co-doping with the charge compensators R+ (Li, Na, K) which partially substitute for Ca2+ crystal sites. CL spectra show that Eu3+ ions were excited by the plasma produced by the incident electrons and the CL properties of Ca2Ge7O16:Eu-3+,Eu- Li+ as a function of accelerating voltage and probe current were investigated. Ca2Ge7O16:Eu3+ phosphor offers higher thermal stability compared with the commercial red phosphor Y2O3:Eu3+. The results indicate that Ca2Ge7O16:Eu3+ can be a suitable red-emitting phosphor candidate for FEDs and w-LEDs. (C) 2014 Elsevier Ltd. All rights reserved.