SYNTHESIS OF CHEMICALLY MODIFIED METAL OXIDE NANOPARTICLES FOR NOVEL APPLICATIONS

Abstract

Doped wide band gap metal oxides are among the best candidates for dilute magnetic semiconductors (DMS) due to coupling of electronic and magnetic properties. They have wide range of technologically important applications in different fields, such as gas sensors, solar cells, varistors, light emitting devices, photocatalyst, antibacterial activity and cancer treatment. A number of methods have been used so far for the synthesis of transition metal doped ZnO nanoparticles such as, autocombustion method, ball milling, co-precipitation, sol-gel, hydrothermal route, etc. Herein, a strategy is reported for the suppression of charge carrier recombination rate and enhancement of photocatalytic efficiency by introducing transition metal as a dopant and surface modification with arginine. In the present report, synthesis and characterization of Cu (II) doped ZnO nanoparticles via co-precipitation method by varying the concentration of the dopant have been carried out. The functionalized nanoparticles were used for the photocatalytic degradation of methyl orange. Nanocomposites are multiphase materials with atleast one of the phases in nanometer range and possess multifunctional properties. Mixed oxides find extensive applications in optical industry and ceramics and as catalysts and catalyst support materials. They exhibit high thermal stability, surface acidity, porosity, surface area and catalytic activity. Different methods like mechanical mixing, co-precipitation, sol-gel, etc, have been used to prepare nanocomposites. In the present report, synthesis and characterization of SiO2-Al2O3 nanocomposite have been carried out via sol-gel method with post functionalization with 3-mercaptopropyltrimethoxysilane. The modified nanocomposite was used for the adsorption of methyl green dye. The prepared nanoparticles were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray analysis (EDXA), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), photoluminescence (PL) spectroscopy, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The optical properties were investigated by using diffuse reflectance spectroscopy (DRS) and Dynamic Light Scattering (DLS).