(198m) Green Synthesis of Copper Oxide Nanoparticles Using a Simple Microwave-Assisted Method

In this study, a facile microwave-assisted synthesis method for colloidal copper oxide nanoparticles (CuNPs) has been designed using an environmentally benign approach with glucose and starch as the reducing and capping agents. The electrical, catalytic, sensing and surface properties of copper based nanomaterials find increasing applications in conductive films, supercapacitors, nanofluids, catalysis and as a potential antimicrobial agent. Due to their low cost and unique properties copper based nanoparticles are good candidates for the afore mentioned applications. Stability is of crucial importance for synthesis of colloidal nanoparticles. Without proper protection, the CuNPs tend to aggregate severely. Stable CuNPs were obtained using starch as a capping agent resulting into small-sized nanoparticles preventing their aggregation. The colloidal CuNPs produced were characterized using X- ray diffraction (XRD), scanning electron microscopy (SEM), UV- visible spectrophotometry and inductively coupled plasma-atomic emission spectrometry (ICP- AES); where the crystalline structure and size of the CuNPs was confirmed by XRD peaks, SEM analysis provided the morphology of prepared nanoparticles, Surface Plasmon Resonance (SPR) of the synthesized CuNPs obtained by UV–Vis spectroscopy showed the reduction of copper ions and reaction conversion. Also, to study the reaction yield, unreacted copper was detected by ICP-AES. We further looked at potential electronic applications of the nanoparticles which were studied using cyclic voltammetry (CV). The effects of temperature, pressure, time, power requirement and molar concentrations of reactants were studied to fix the conditions of the reaction system. We have explored a possible mechanism for the reaction, along with an energy balance on the system, thereby identifying a scope for development of standardized technology using microwave and biodegradable sugars for synthesis of oxide, bimetallic and alloy nanoparticles. Prospective applications in catalysis and bio-sensing will be explored.

Keywords: Copper oxide nanoparticles, microwave, green method