Tailoring Structural and Electrochemical Properties of Composite Ni-Based Electrocoatings

Oxygen electroevolution reaction (OER) was studied in alkaline medium on the Ni-P+TiO2composite electrocoatings obtained from the Watts type bath containing the suspension of TiO2particles. The comparable Ni-P coatings were electrodeposited from the supporting electrolyte without titanium dioxide. The galvanostatic electrodeposition of all coatings was conducted on a polycrystalline copper substrate at the deposition current density of 240 mA cm-2for 30 min. The electrolysis process was carried out at temperatures of 293-333 K. It was found that the mass increment and the content of TiO2in the obtained coatings is a decreasing function of the electrodeposition temperature. It was also acertained that the built-in TiO2as the composite component into the Ni-P matrix has no effect on the improvement of the electrocatalytic properties of the Ni-P+TiO2composite electrodes towards OER probably due to limitation of the size of the electrochemically active surface area of the electrode material obtained under proposed conditions.