Influence of Substrate Preparation on the Catalytic Activity of Conical Ni Catalysts

The production of hydrogen using electrolysis contributes to the development of more important renewable energy sources. Nowadays, the synthesis of alloys, which can be successfully applied as catalysts instead of precious metals, is carefully investigated. One-step electrodeposition is a surface engineering method that allows for the control of the morphology of the deposit by changing deposition parameters. It is a simple and low-cost process based on electrochemical synthesis from electrolytes, usually non-toxic crystal modifiers. In this work, a conical Ni structure on Cu foil was produced using this technique. The effect of the copper substrate on the morphology of the developed nanocones was analyzed using a Scanning Electron Microscope (SEM). Then, the catalytic performance of the synthesized coatings was carefully analyzed based on the results of a linear sweep voltammetry experiment and the measurements of their wettability and electrochemical active surface area. The proposed method of Cu treatment, including polishing with sandpapers, influenced the growth of cones and, consequently, increased the catalytic activity and active surface area of the Ni coatings in comparison to the bulk Ni sample.