Synthesis and luminescence properties of Yb3+ and Er3+ doped KLa(WO4)2 nanoparticles

The luminescent nanocrystalline Yb3+ and Er3+ codoped KLa(WO4)2 has been prepared by Pechini method. X-ray diffraction and transmission electron microscope were used to study the structure of the obtained samples. The average grain size of these samples depended on the annealing temperature, increasing with the increase of the temperature. The cell parameters and the crystallite size of KYbxEr0.02La0.98−x(WO4)2 nanocrystalline decreased with the increase of x value. Luminescence studies showed that the intensity of upconversion emission of the Yb3+ and Er3+ codoped samples was much stronger than that of the Er3+ single doped samples (pumped by 980 nm LD). The upconversion emission mechanisms suggested that all the three bands of upconversion emissions were two-photon process.