Effect of TiO2 nanoparticles on hydrogen evolution reaction activity of Ni coatings

Abstract

The electrocatalytic activity of electrodeposited Ni and Ni–TiO<inf>2</inf> coatings with regard to the alkaline hydrogen evolution reaction (HER) was investigated. The Ni coatings were electrodeposited from an acid chloride bath at different current densities, and their HER activities were examined in a 1.0-mol·L-1 KOH medium. The variations in the HER activity of the Ni coatings with changes in surface morphology and composition were examined via the electrochemical dissolution and incorporation of nanoparticles. Electrochemical analysis methods were used to monitor the HER activity of the test electrodes; this activity was confirmed via the quantification of gases that evolved during the analysis. The obtained results demonstrated that the Ni–TiO<inf>2</inf> nanocomposite test electrode exhibited maximum activity toward the alkaline HER. The surface appearance, composition, and the phase structure of all developed coatings were analyzed using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD), respectively. The improvement in the electrocatalytic activity of Ni–TiO<inf>2</inf> nanocomposite coating toward HER was attributed to the variation in surface morphology and increased number of active sites. © 2018, University of Science and Technology Beijing and Springer-Verlag GmbH Germany, part of Springer Nature.