A Red-Emitting Phosphor Rb2TaF7:Mn4+ for White Light-Emitting Diodes

Abstract

Herein, a new red phosphor Rb2TaF7:Mn4+ was prepared by the co-precipitation method. Under excitation of the blue light at 468 nm, this phosphor exhibits a series of red-emitting peaks, due to the 2E→4A2 transitions of Mn4+. It is worth mentioning that an intense zero-phonon line (ZPL) of Mn4+ appears at 620 nm in this non-equivalent Mn4+ doping system. A white light-emitting diode (w-LED) based on the Rb2TaF7:Mn4+ (1.0 mol%) phosphor emits bright white light with a color temperature (T c) of 4387 K and a color rendering index (Ra) of 88, showing its potential application in w-LEDs.