Nickel-Borate/Reduced Graphene Oxide Nanohybrid: A Robust and Efficient Electrocatalyst for Oxygen Evolution Reaction in Alkaline and Near Neutral Media

Designing highly active electrocatalysts with cost-effective transition metals for oxygen evolution reaction (OER) is of vital significance for multifarious energy conversion and storage devices. Herein, a facile in situ co-reduction method was applied for the preparation of nickel-borate nanoparticle on reduced graphene oxide (Ni-B-i/RGO) with high surface active sites exposure yield and reinforced electron transfer ability. Such Ni-B-i/RGO nanohybrid shows high catalytic activity with overpotential of 329mV to drive a geometrical current density of 10mAcm(-2) and Tafel slop of 79mVdec(-1) in 1m KOH. Moreover, this Ni-B-i/RGO nanohybrid also displays excellent performance under near neutral condition, with a low onset potential of 352mV and Tafel slop of 176mVdec(-1) in 0.1m potassium borate (KBi, pH9.2), better than most of Ni-based OER catalysts. Our research has paved a facile path for the development of highly active electrocatalysts.