Electroless plated Ni-B-x films as highly active electrocatalysts for hydrogen production from water over a wide pH range

The performance of electroless plated Ni-B-x films was studied in a wide pH range for the hydrogen evolution reaction (HER). The atomic ratio of B to Ni has great influence on the particle size and the morphology of Ni-B-x, materials, and more importantly on the catalytic H2 evolution property of Ni-B-x films. The film with a B:Ni atomic ratio of 0.54, denoted as Ni-B0.54, displayed the best performance with a current density of 10 mA cm(-2) at very low over potentials (eta) of 45 mV in 0.5 M H2SO4, 54 mV in 1.0 M pH 7 phosphate buffer solution (PBS), and 135 mV in 1.0 M KOH, and the catalytic activity maintained over 20-h electrolysis at 11=100 mV in all tested media of different pH values. The Tafel slopes of the Ni-B-0.54 film are 43, 77, and 88 mV dec(-1) in 0.5 M H2SO4; 1.0 M neutral PBS, and 1.0 M KOH, respectively. These results show that the combination of earth -abundant nickel and boron elements in an optimal B-to-Ni atomic ratio can provide highly active and stable electrocatalysts for the HER over a wide pH range. (C) 2015 Elsevier Ltd. All rights reserved.