Platinum is often used as a catalyst in ethanol electrooxidation. Still, it has many disadvantages being expensive and its active site can be poisoned by CO. Transition metal of Co and Ni can become a catalyst in alcohol electrooxidation at a lower cost to synthesize. In this work, bimetallic CoNi were successfully prepared by electrodeposition method with different Co/Ni ratios to enhance ethanol electrooxidation. Samples of CoNi are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and electrochemical impedance spectroscopy (EIS). XRD diffractogram confirmed the formation of CoNi. Morphology of CoNi in SEM characterization showed that CoNi with ratio 5:1 has the more dispersed particle and the greatest surface area. EDX characterization indicated that the relative weight of different Co/Ni ratios, the composition wt.% Co is 81.15% and wt.% Ni is 18.85% in CoNi 5:1, wt.% Co is 60.96% and wt.% Ni is 30.94% in CoNi 2:5, while wt.% Co is 50.19%, and wt.% Ni is 49.81% in CoNi 5:5. EIS characterization showed that CoNi with ratio of 5:1 has faster electron kinetics. Electrooxidation of ethanol used cyclic voltammetry (CV) method. The best results from the ethanol electrooxidation reaction were obtained for CoNi with a ratio of 5:1 because of the greatest surface area that showed in scanning electron microscopy and fast electron transfer kinetics compared to others ratio of CoxNiy.

Gold nanoparticles (AuNPs) were found to act as antioxidants owing to their inert, high stability, biocompatibility, and non-cytotoxic. The present investigation involved the synthesis of gold nanoparticles through the electrodeposition technique on a substrate comprising Fluorine-doped Tin Oxide (FTO). By manipulating the scan rate parameter, an effective approach can be employed to facilitate precise management of particle morphology and size. The obtained shape of AuNPs were spherical and irregular. In this study, it was observed that gold nanoparticles elicited potent inhibition, particularly at a scan rate of 150 mV/s, with a markedly high inhibition value of 41.27%. The outcome was further supported by an augmented particle distribution density per unit area, which measured as 149,635,036.5/mm².