Enhanced hydrogen evolution on NiCoMn trimetallic alloy electrode fabricated via laser-patterned copper substrate

High-performance electrocatalysts are key to increasing hydrogen generation from alkaline water electrolysis, an important technology to enable clean, renewable energy systems. Here, we report the important role of laser treatment of metal substrates to enhance the performance of electrocatalysts for the hydrogen evolution reaction (HER). Electrocatalyst synthesis involves a two-step procedure: laser patterning of copper foil (CuF) substrates, followed by electrodeposition of a NiCoMn ternary alloy, resulting in the final NiCoMn@LP-CuF electrocatalyst. Laser pattering of the Cu substrate increases the active surface area and is expected to improve interfacial adhesion of the NiCoMn deposit, thus promoting the kinetics of the HER reaction. The laser-patterned electrocatalyst NiCoMn@LP-CuF shows excellent electrochemical HER performance in alkaline media, requiring an overpotential of 149 mV at 10 mA cm⁻² for HER in 1 M KOH, which is lower compared to the laser-untreated electrocatalyst (NiCoMn@CuF). The electrodeposition of NiCoMn on laser-treated CuF substrate sustains catalytic activity and adheres to the catalyst, preventing catalyst detachment. Additionally, electrochemical stability testing at constant current densities of 10 mA cm⁻² and 50 mA cm⁻² shows that the catalyst degradation remains negligible, confirming its suitability for continuous hydrogen production. Furthermore, the NiCoMn@LP-CuF electrode allows for efficient two-electrode stability, achieving overall water splitting at 1.66 V for 10 mAcm⁻² for 30 h. These enhancements in electrocatalytic activity are attributed to the optimal electronic conductivity, enhanced surface area, electrolyte accessibility, mass transfer across the electrode-electrolyte interface, and optimized mass transfer in the electrode. This research demonstrates the potential of ternary alloy catalysts and laser-patterned substrates for large-scale, cost-effective hydrogen production.