Shape controllable synthesis and enhanced upconversion photoluminescence of β-NaGdF4:Yb3+, Er3+ nanocrystals by introducing Mg2+

Shape controllable synthesis and enhanced upconversion photoluminescence of β-NaGdF₄:Yb³⁺, Er³⁺ nanocrystals by introducing Mg²⁺

Yang Yong-Xin^{1, 2}, Xu Zheng^{1, 2, †}, Zhao Su-Ling^{1, 2}, Liang Zhi-Qin^{1, 2}, Zhu Wei^{1, 2}, Zhang Jun-Jie^{1, 2}

(color online) (a) UC luminescence spectra of the samples after doping various concentrations of Mg²⁺ ions into the NaGdF₄:20-mol% Yb³⁺, 2-mol% Er³⁺ matrix: x-mol% Mg²⁺ ions under diode laser excitation at 980 nm (x = 0, 40, 50, 60, 70). (b) Red, green, and total UC emission intensities versus Mg²⁺ doping content.