Photoluminescence properties of Eu${}^{3+}$ doped CaSr(WO${}_4$)${}_2$ phosphor by Li${}^{+}$ charge compensation

A series of CaSr(WO${}_4$)${}_2$: Eu${}^{3+}$ and CaSr(WO${}_4$)${}_2$: Eu${}^{3+}$, Li${}^{+}$ phosphors with different Eu${}^{3+}$ or Eu${}^{3+}$/Li${}^{+}$ molar contents were successfully synthesized by high-temperature solid-state reaction. Through a series of characterization methods, the composition, structure and luminescence characteristics of the sample are obtained. Upon excitation at 393 nm, the strong red light corresponding to the ${}^5$D${}_0$ → ${}^7$F${}_2$ transition of Eu${}^{3+}$ can be observed. The effect of Li${}^{+}$ charge compensation on the photoluminescence of the sample is studied. The strongest red emission is obtained through 1% Eu${}^{3+}$ and 1% Li${}^{+}$ doping. All of the results indicate that Li${}^{+}$ charge compensation can effectively enhance the red emissions intensity of Eu${}^{3+}$-doped CaSr(WO${}_4$)${}_2$ phosphors.