Enhanced Up-Conversion of High Concentration Yb3+/Er3+ Doped β-NaYF4 Microparticles by Changing the Host Matrix

Abstract

With the aim of improving the up-conversion luminescence intensity of high concentration Yb3+ /Er3+ doped microparticles, Yb³⁺ /Er³⁺ doped β-NaYF₄/β-NaLuF₄/β-NaYbF₄samples were prepared by the hydrothermal method. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to characterize the crystal structure and morphology. Intense blue emission (² H_{11/2 →} ⁴ I_15/2, ⁴ S_{3/2 →} ⁴ I^15/2) and red emission (⁴ F_{9/2 →} ⁴ I_15/2) of Er³⁺  were observed under 980 nm excitation. When the doping concentrations of Yb³⁺  and Er³⁺  were high, the up-conversion luminescence intensity using b-NaYbF4 as the host matrix was enhanced, and in the experiment the sample NaYbF₄:16 mol.% Yb³+ /32 mol% Er³+ with b- NaYbF₄ as the host matrix has the strongest luminescence.