A cost-effective and efficient electrocatalyst for the oxygen evolution reaction during the electrolysis of water is highly desired. In an effort to develop an economical material for replacing precious-metal-based catalysts, a novel and self-standing amorphous ultrathin nanosheet (NS) of bimetallic iron-nickel boride (Fe-Ni-B NSs) on Ni foam is presented, which displays a better oxygen-evolving activity compared to the precious-metal catalyst RuO . In 1.0 m KOH electrolyte solution, it requires an overpotential of only 237 mV to reach a current density of 10 mA cm with a small Tafel slope of 38 mV dec and shows prominent long-term electrochemical stability. A synergistic effect between highly abundant catalytically active sites on the 3D porous substrate improved the electron transport arising from the presence of highly negative boron, and the high conductivity of the substrate results in an outstanding electrocatalytic activity. The advanced catalytic activity, facile electrode fabrication, and low costs make it a potential oxygen-evolving material, which may be extended to other energy-conversion and storage technologies.

Metal borides represent an emerging family of advanced electrocatalyst for oxygen evolution reaction (OER). Herein, we present a fast and simple method of synthesizing iron-doped amorphous nickel boride on reduced graphene oxide (rGO) sheets. The hybrid exhibits outstanding OER performance and stability in prolonged OER operation. In 1.0 M KOH, only 230 mV is required to afford a current density of 15 mA cm −2 with a small Tafel slope of 50 mV dec −1 . DFT calculations lead to a suggestion that the in situ formation of MO x H y during electrochemical activation acts as active sites for water oxidation. The superior OER activity of the as-prepared catalyst is attributed to (i) its unique amorphous structure to allow abundant active sites, (ii) synergistic effect of constituents, and (iii) strong coupling of active material and highly conductive rGO. This work not only provides new perspectives to design a highly effective material for OER but also opens a promising avenue to tailor the electrochemical properties of metal borides, which could be extended to other materials for energy storage and conversion technologies.

Hydrogen production with high purity through water splitting has been proved to be a potential energy technology but requires highly efficient, low cost, and robust electrocatalysts. Herein, a tungsten−nickel/nickel foam hybrid is prepared by a facile method and exhibits an outstanding hydrogen evolution reaction activity and remarkable stability in alkaline solution. It only requires an overpotential of 36 mV to afford the current density of 10 mA cm −2 with a small Tafel slope of 43 mV dec −1 . Owing to the excellent electrocatalytic performance arising from the synergistic effect of binary tungsten−nickel interacting through the d-orbital electron transfer, the as-prepared material is the best among tungsten-based HER electrocatalysts. The lower adsorption energy of water molecules and a small Gibbs free energy of hydrogen adsorption (0.17 eV) on tungsten atoms of WNi (111) from DFT calculations reveal the favorable water electrolysis kinetics. Moreover, the simple preparation strategy can be extended to design of other active materials for clean energy technology applications and beyond.