Hydrogen is a renewable energy source that is considered among the candidate alternatives to fossil fuels. In this research, dendrite Nisingle bondCu coating is the electrodeposited and catalytic performance of this electrode is investigated toward hydrogen evolution reaction (HER) in 1.0 M KOH. The response surface methodology (RSM) as the design of experimental (DOE) method is used for optimizing the intrinsic electrocatalytic HER activity (Nisingle bondCu A) and active surface area (Nisingle bondCu B) of the dendrite Nisingle bondCu coating. The DOE results showed that the active surface area had a stronger effect on the electrocatalyst HER activity than the intrinsic parameter. The η10 (overpotential at 10 mA cm−2) and Tafel slope of the Nisingle bondCu B electrode were 202 mV vs. RHE and 82 mV dec−1, respectively. According to the Tafel slope of the optimized Nisingle bondCu B electrode, the Volmer-Heyrovsky mechanism predominated the HER mechanism. The Nisingle bondCu B electrode showed high electrocatalytic activity and electrochemical stability compared to recently proposed catalysts. The electrocatalyst stability of the Nisingle bondCu B electrode led to the small size of the H2 bubble on the surface of the electrode. The low size and rapid detachment of the H2 gas bubbles resulted in the dendrite Nisingle bondCu B structure.

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