Influence of O2 flow rate on the electrochemical hydrogen evolution reaction performance of Cu/Cu2O/Grade stainless steel prepared by RF magnetron sputtering

초록

The exploration of cost-effective and high-efficiency electrocatalysts for alkaline hydrogen evolution reaction (HER) is essential in tackling issues caused by carbon dioxide emissions. Cu2O-based nanomaterials were evaluated as potential competitors to alter noble metal electrocatalysts for HER as a result of their low cost, abundance, and adjustable catalytic activities. In this study, Cu/Cu2O nanostructures were deposited on commercial stainless steel (SS) via a vacuum deposition technique of radio frequency magnetron sputtering. The influence of various O2 flow rates, including 5, 10, 15, and 20 sccm on the morphological structure and elemental ratio of Cu/O were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), and Energy-dispersive X-ray spectroscopy (EDS). More importantly, the change in O2 flow rates optimized HER efficiency and indicated that the optimal sample of Cu/Cu2O/SS-10 provided better HER catalytic properties than that of the bare SS. In particular, this electrode required a low overpotential of 292 mV to achieve a current density of 10 mA cm−2 and outstanding durability with 43200 s continuous hydrogen production. The high efficiency is attributed to the synergistic effect of the Cu2O and Cu metal components and the high electrical conductivity of commercial SS, which benefits dissociative H2O adsorption, adsorbed hydrogen recombination, and accelerating charge transfer in the catalytic process. This study could provide a straightforward and sustainable approach for preparing precious metal-free electrodes for alkaline water electrolysis. © 2025 Elsevier B.V.

키워드