چكيده به لاتين
In this thesis, bismuthate nanostructures of transition metals, including ZnBi38O58, Cd3Bi10O20, CuBi2O4/Bi3ClO4 and NiO/Bi2O3/Bi3ClO4 using auto-combustion sol-gel and pechini sol-gel methods were prepared. In the auto-combustion method for the preparation of ZnBi38O58 and Cd3Bi10O20 nanostructures, the effect of type of fuel and capping agents, type of pH regulators and mole ratio of fuel to total metals were investigated. Also, in the pechini method for the preparation of CuBi2O4/Bi3ClO4 and NiO/Bi2O3/Bi3ClO4 nanocomposites, the effect of the type of acid and complexing agents, the type of gelling agents and the mole ratio of acid to total metals were evaluated. The results showed that each of these parameters have a significant effect on the purity, particle size and morphology of the final products, and the product with desirable properties can be achieved by controlling these parameters. In the next step, the photocatalytic activity of the prepared nanostructures and nanocomposites was evaluated for the degradation of mono/diazo dyes under visible light illumination. The photodegradation efficiency over 90% of azo dyes under visible light illumination by utilizing of the mentioned nanostructures, introduces these compounds as suitable candidates for photocatalytic applications under visible light irradiation. The as-synthesized products were characterized by powder X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible (UV-Vis) spectrophotometer, thermal gravimetric analysis (TGA) and energy dispersive X-ray (EDX) techniques.
