A Suitable Porous Micro/Nanostructured Cu and Cu–Ni Film: Evaluation of Electrodeposition Behavior, Electrocatalytic Activity, and Surface Characterization of Porous Film

Abstract

Selecting an appropriate catalyst with a high surface area and proper electron transfer ability can accelerate improved hierarchical catalysts. In this research, an appropriate porous film was formed by the dynamic hydrogen bubble template (DHBT) method with a pulse current (PC) electrodeposition. CH3COOH was added to the Cu electrodeposition bath as a non-ionic surfactant, CTAB was added as a cationic surfactant, and Ni was added as an alloying element. Results show the formation of a nano-dendritic porous Cu film. The presence of surfactants, especially CTAB, causes dendritic arms to be more elegant and denser, with more round voids. Furthermore, adding Ni sulfate to the bath containing both surfactants resulted in a porous Cu film with the most improved HER behavior by decreasing the overpotential (η 10) from 389 to 195 mV RHE−1 and the Tafel slope from 174 to 93 mV dec−1 in a 1.0 M KOH solution. According to the results of the electrochemical active surface area (ECSA), normalized LSV curves, and charge transfer resistances, the co-deposition of Cu and Ni revealed more active surface area and improved intrinsic HER catalytic activity. Therefore, these properties can convince researchers to utilize an improved porous Cu–Ni electrode for energy applications.