Evaluation of photocatalytic and supercapacitor potential of nickel tungstate nanoparticles synthesized by electrochemical method

Nickel tungstate nanoparticles (NiWO4 NPs) that were synthesized by an electrochemical method under various reaction conditions, namely, different tungstate ion concentrations, voltages, temperatures, and stirring rates, were studied here. These NPs were characterized using FT-IR, XRD, SEM, and thermal analysis techniques. The application of the NiWO4 NPs as an excellent photocatalyst was investigated via the degradation of methyl orange (MO) under illumination with UV radiation. The maximum conversion of MO reached about 87% after 100 min. Furthermore, the electrochemical properties were investigated using cyclic voltammetry (CV), galvanostatic charge-discharge, electrochemical impedance spectroscopy (EIS) and continuous cyclic voltammetry (CCV) in 3.0 M H2SO4 as the electrolyte. The electrochemical investigations revealed that an NiWO4 electrode displayed enhanced supercapacitive performance, including a specific capacitance of 468 F g(-1) at a scan rate of 2 mV s(-1). Furthermore, CCV measurements showed that the NiWO4 electrode retained 102.2% of its initial capacitance after 4000 cycles.