An industry-applicable hybrid electrode for large current density hydrogen evolution reaction

The performance evaluation on water splitting electrodes is usually conducted in laboratory at current density range of 10–100 mA cm⁻², and this is far from satisfactory for the industrial practices that require the operating current density larger than 400 mA cm⁻². In this work, an efficient hybrid electrode is developed by firstly electro-etching the nickel mesh (E-NM) in actual seawater and then in-situ depositing nickel nanowires (NWs) onto E-NM substrate under the externally applied magnetic field. The results show that NWs are integrated into the defective E-NM structure. The assembled NWs/E-NM hybrid electrode achieves a high current density of 800 mA cm⁻² at 2.0–2.1 V, which outperforms the commercial NM electrode. Moreover, the current density does not decay after 100 h stability test at 500 mA cm⁻².