Enhanced photoluminescence of GdPO4:Tb3+ under VUV excitation by controlling ZnO content and annealing temperature

High-quality Zn-free and added GdPO4:Tb3 green phosphors, i.e., fine size as well as smooth and spherical morphologies, were synthesized by ultrasonic spray pyrolysis. The influence of Zn2+ content and annealing temperature on the photoluminescence properties of the GdPO4:Tb3 phosphors annealed at 800–1100 °C was investigated. The addition of Zn2+ for Gd3+ was highly effective for improving the photoluminescence properties of GdPO4:Tb3. The Zn added GdPO4:Tb3 phosphors with Zn/Gd = 0.045/0.805 showed the strongest emission of the prepared phosphors. The emission intensity at 544 nm for the GdPO4:Tb3 phosphors with Zn/Gd = 0.045/0.805 annealed at 900 °C was 496% stronger than that at 800 °C.

► We synthesize high-quality Zn-free and added GdPO4:Tb3 green phosphors.
► The emission intensity depends strongly on the Zn2+ content and the annealing temperature.
► The addition of Zn2+ for Gd3+ is highly effective for improving the photoluminescence properties of GdPO4:Tb3.