Color tunable cathodoluminescence properties of RE2WO6:Ln3+ (RE, Ln = Er3+ and Tm3+) phosphor and its microscopic imaging

Highly crystalline RE2-xWO6:xLn3+ (RE, Ln = Er3+ and Tm3+, x = 0.02 to 0.50 mol.) phosphors were successfully synthesized by the solid-state reaction method. The cathodoluminescence (CL) properties of the RE2-xWO6:xLn3+ phosphors were studied in detail by changing the Ln3+ (Er, Tm) doping concentration, accelerating voltage and tuning the electron beam current. The CL spectra of the undoped Er2WO6 phosphor showed bright red emission due to the 4F9/2→4I15/2 (Er3+) transition, while Tm3+ doped Er2WO6 display the strong green emission due to 4S3/2→4I15/2 (Er3+) transitions. The Er3+ doped Tm2WO6 phosphor showed strong white light emission due to the combination of several bands in the CL spectra. The CL emission intensity of the phosphors linearly enhanced when the electron beam current was increased from 1.00 nA to 7.0 nA and no saturation emission was noted in this range. The Commission Internationale del’Eclairage chromaticity coordinates were measured for the RE2WO6:Ln3+ phosphors.