Facile Synthesis of Nickel Oxide/Delaminated Boron Composite with an Enhanced Electrocatalytic Activity Towards the Oxygen Evolution Reaction in Alkaline Medium

Over the years, there has been a surge in the quest for the replacement of noble metal-based electrocatalysts for the efficient oxygen evolution reaction (OER) in an alkaline medium. Herein, a facile synthesis of NiO/delaminated boron composite and its electrocatalytic activity is reported. The influence of the loading level of delaminated boron on the electrocatalytic OER activity of NiO in 1 M KOH medium is investigated systematically. The linear voltammetry study reveals that all NiO/delaminated boron (NiO-B-_X) composites demonstrate a higher current density response as well as lower overpotential compared to NiO. The presence of the borophene in the composite could have resulted in the introduction of positive charge carriers on NiO, thereby improving the kinetics of the OER. Besides, the dispersion of the NiO particles onto the surface of delaminated boron is expected to mitigate the aggregation of NiO particles and expose a larger number of electrochemically active sites, consequently enhancing the overall OER performance. Evidently, NiO-B-_X electrocatalysts prepared with 10 mg of the borophene, (NiO-B-₁₀), demonstrate both the lowest overpotential at 10 mA cm⁻² of 1.61 V and Tafel slope of 61.25 mV dec⁻¹. It also exhibits extended stability over 8 h.

Graphical Abstract