Enhanced photoluminescence of red-emitting KCa(PO3)3: Eu3+ phosphors by charge compensation

Abstract The traditional solid-state reaction method was employed to prepare the KCa(PO3)3: Eu3+ red-emitting phosphors. The emphasis of this work lies in the charge-compensation effects produced by monovalent alkali ion M+ (M = Li, Na, and K) on the luminescence properties. With the nonequivalent substitution of Eu3+ ion for Ca2+ ion, Ca2+ vacancy was inevitably produced, which had negatively effects on luminescence intensity. In this case, the monovalent alkali ions, acting as charge compensators, were introduced into the host. Compared to the uncompensated sample, M+ co-doped samples had remarkable enhancement on luminescence intensity with the most intense emission for Na+ ion compensation. Besides, KCa(PO3)3: Eu3+ has a good chromaticity coordinates (0.643, 0.357) along with an incredibly high quantum efficiency (nearly 100%), indicating its potential applications in w-LEDs.