One step electrochemical fabrication of high performance Ni@Fe-doped Ni(oxy)hydroxide anode for practical alkaline water electrolysis

Oxygen evolution reaction (OER) is a rate-determining process in alkaline water electrolysis (AWE). Herein, we report a novel one-step oxidation-electrodeposition (OSOE) approach to generate core@shell nanoarrays-based AWE electrode with outstanding OER performances: an overpotential of 245 mV at 10 mA cm(-2) (Tafel slope: 37 mV dec(-1)), and excellent stability under huge current densities. Moreover, the alkaline (AEL) cell equipped with NM-OSOE-23 anode recorded significant performance improvement of 200 mV lower voltage (2 A cm(-1)) compared with a similar cell used bare Ni mesh as an anode, which was contributed by notable enhancements of interface contact, anodic charge transfer, and mass transfer. These promising results are attributed to the constructed specific core@shell Ni@Fe-doped Ni(oxy)hydroxide nanoarray architecture on commercial nickel mesh. This study demonstrates this first reported OSOE can be commercialized to make highly efficient anodes enabling next-generation AWE.

Automated summary

This study reports a one-step oxidation-electrodeposition method to generate core@shell nanoarrays-based alkaline water electrolysis (AWE) electrode with outstanding oxygen evolution reaction (OER) performances. The electrode shows low overpotential and excellent stability under high current densities. The AEL cell equipped with this electrode demonstrates significant performance improvement compared to a similar cell using a bare Ni mesh as an anode. The results are attributed to the specific core@shell Ni@Fe-doped Ni(oxy)hydroxide nanoarray architecture.