Y Hanifehpour - Department of Chemistry, Sayyed Jamaleddin Asadabadi University, Asadabad, Iran

Nowadays, water contamination and world energy crisis have attracted much amused attention among scientific communities. Recently, modified Ln۳+-doped semiconductors have been used as effective catalyst by controlling the recombination probability of produced electron-hole pairs in semiconductors In this study, Yb-doped PbTe nanoparticles with variable Yb۳+ content were synthesized by a simple hydrothermal technique. The synthesized nanoparticles were characterized by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and powder X-ray diffraction (XRD). The XRD patterns indicated that the particles wereexcellently crystallized due to the cubic PbTe phase. The SEM images certify that the substitution of Yb into the lattice of PbTe does not change the morphology of PbTe nanoparticles. The SEM images displayed that the size of the particles was in the range of ۲۰-۷۰ nm. The energy of the bandgap of doped-PbTe and PbTe nanoparticles expected from the chief absorption edges of the UV-Vis diffuse reflectance spectrum. Blue shifts in DRS spectra of PbTe were noticed by increasing the concentration of the Yb۳+ ions. The incorporation of Yb۳+ into the PbTe lattice was confirmed by the XPS technique. The electrical conductance of various Tb-doped PbTe samples is higher than that for the pure PbTe, and elevates with temperature. The photocatalytic performance of Yb-doped PbTe compounds was determined as well by Malachite green (MG) degradation under visible light irradiation. Improved photocatalytic activity was shown for Yb-doped CdTe with ۰.۱mol Yb dopant. Considering radical scavengers, the sequence of inhibitory effect was ۱, ۴ Benzoquinone ˃ I− ˃ t-BuOH ˃ C۲O۴۲-. The influence of various specifications like catalyst amount, primary dye concentration, and ultrasonic power were explored. The enhanced photocatalytic performance can be attributed to the electron transfer between Yb۳+ and PbTe by introduction of an Yb ۴f level.