Simultaneous production of green hydrogen and decontamination of dye wastewater using WSe2–CuO/graphite electrochemical cell

Abstract

For the circular economy approach to wastewater treatment, recycling dye-contaminated wastewater while simultaneously producing green hydrogen (H2) is deemed appropriate. The electrodes used in the wastewater electrolysis process were made of cent percent recyclable and environmentally benign graphite rod, cellulose paper, and WSe2–CuO electrocatalyst. Anode-side breakdown of organic dyes with a 95% degradation efficiency and cathode-side generation of green hydrogen have both been accomplished simultaneously. The as-prepared electrocatalyst were analysed using X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). WSe2–CuO electrocatalyst exhibits excellent electrochemical performance i.e. overpotential (141 mV at −10 mA cm−2), Tafel slope (80 mV dec−1) and double layered capacitance (32.4 mF cm−2). Furthermore, a fast charge transfer activity, and stability of the electrocatalyst were observed through electrochemical impedance spectroscopy (EIS), and chronopotentiometry (over 20 h), respectively. A pressing need for technology development in the direction of circular sustainability may be seen in the strong demand for green hydrogen production, where the process can use industrial wastewater.