Facile Deposition of a Spherical Ruthenium-Cobalt Alloy on Nickel Foam as a High-Performance Electrocatalyst for Alkaline Hydrogen Production

Alkaline water electrolysis has the potential to become an important method for producing green hydrogen and achieving net-zero carbon emissions. Consequently, the development of catalysts with higher catalytic values for the hydrogen evolution reaction (HER) is essential for advancing the water-splitting technology. This study introduces a facile deposition strategy using aerosol-assisted chemical vapor deposition to fabricate a bimetallic RuCo alloy on nickel foam (NF), which serves as a Pt-free, high-performance HER catalyst under alkaline conditions. The synergy between Co and Ru, along with the structural advantages of RuCo@NF, significantly enhances the electrocatalytic performance. The optimized RuCo@NF catalyst exhibited HER activity, achieving current densities of 10 and 100 mA cm^-2 at low overpotentials of 17 and 100 mV, respectively. Moreover, it had a minimal Tafel slope of 42 mV dec^-1 and demonstrated stability over 24 h, surpassing that of the benchmark Pt/C catalyst when measured in 1.0 M KOH. Furthermore, density functional theory analysis validated the experimental results, revealing a lower Gibbs free energy value for the RuCo alloy (−0.35 eV) compared to that of metallic Ru (−0.50 eV) and Co (−0.57 eV) in the HER process. This study presents a convenient pathway for the development of a highly active and robust bimetallic thin-film electrocatalyst, demonstrating its potential for hydrogen production in fuel cells.