Fabrication of graphene oxide metal / metal oxide based nanocomposite for electrochemical sensor, photoelectrochemical fuel cell and bioplastic applications

This research explores the synthesis, characterization, and potential applications of graphene oxide (GO) metal/metal oxide nanocomposites. These nanocomposites have garnered significant attention due to their unique properties and potential in various fields. The research is divided into three main parts, each focusing on different applications of nanocomposites. In the first part, GO-silver (rGOAg), GO-nickel oxide (rGONiO), GO-zinc oxide (rGOZnO), and GO-copper oxide (rGOCu2O) nanocomposites were synthesized using photothermal method. Notably, rGONiO exhibited exceptional reversible electrocatalytic activity for 4 Nitrophenols (4NP) reduction with a small separation peak (ΔEp) of 0.087 V. The study confirmed that rGONiO is a suitable nanocomposite for electrochemical sensor that displays an ideal linear relationship between redox current and scan rate. The second part focused on the synthesis of GO- Iron Oxide (rGO-Fe2O3) through microwave irradiation for photoelectrochemical methanol water splitting. The nanocomposite demonstrated superior oxidation of Ferricyanide [Fe(CN)6]3/4 compared to rGO and Fe2O3 alone, suggesting the facilitative role of rGO in enhancing electron transfer during the oxidation process. The photoelectrochemical study revealed a maximum photocurrent density under illumination, emphasizing the potential of rGO-Fe2O3 in promoting methanol oxidation and facilitating water splitting. The final part of the thesis investigated the potential application of GO silver alginate (GOAg/Alg) nanocomposites as bioplastic materials. The nanocomposites were synthesized successfully using a microwave irradiation method and were transformed into thin films through solvent casting. Varying the GOAg content in the nanocomposites resulted in variations in mechanical, thermal, and antibacterial properties. Notably, GOAg/Alg 0.9 exhibited the best overall properties, including high stress resistance, thermal tolerance, low solubility in water, and significant antibacterial activity. Overall, this thesis contributes to the understanding and development of GO metal/metal oxide nanocomposites, highlighting their potential in diverse applications such as electrochemical sensing, photoelectrochemical reactions, and bioplastic materials. The findings underscore the importance of nanocomposite composition in achieving desired properties, paving the way for future advancements in the field.