Preparation and characterization of reduced graphene oxide added ZnO, TiO2 and Ag containing nanocomposite materials

Graphene is a promising material in many different applications in recent years due to its superior mechanical, magnetic, electrical and thermal conductivity properties. Because of these properties, the preparation and investigation of graphene based composite materials for various applications are of great interest. Within the scope of this thesis, the nanocomposite materials containing reduced graphene oxide (rGO) doped ZnO, TiO2 and Ag were synthesized. Graphene oxide (GO) was synthesized from natural graphite with modified Hummer's method in this study due to its low cost of chemical method, high amount of production, non-toxic gas formation and using less chemicals among different methods in graphene production. For this, the non-toxic and antioxidant L-ascorbic acid (L-AA) reductant material was used. Then, binary, ternary and quaternary nanocomposite materials consisting of rGO, ZnO, TiO2 and Ag nanoparticles were produced by ultrasonic-assisted solution process. The prepared GO, rGO, ZnO-rGO, TiO2-rGO, Ag-rGO, ZnO-TiO2-rGO and ZnO-TiO2-Ag-rGO materials were characterized by X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and thermogravimetric analysis (TGA). The results confirmed the hybrid structure of nanocomposite materials and showed their high stability. In addition, antibacterial properties of these materials were investigated by Bacillus subtilis and Escherichia coli bacteria by well diffusion method. Among the prepared nanocomposite materials, ZnO-rGO showed the best activity against both bacteria.