In comparison to oxygen evolution reactions (OER), the urea electrooxidation reactoion (UOR) is a more energy-efficient technique for producing hydrogen. To make this process economically viable, stable and effective electrocatalysts are essential. In two steps, this study created an electrocatalyst for Ni-Fe-Co LDH/Ni-S/NF: Using the dynamic hydrogen bubble template (DHBT) method, a porous Ni-S structure was first electrodeposited on nickel foam (NF). Next, Ni-Fe-Co nanosheets were created via cyclic voltammetry (CV). The electrocatalyst showed excellent activity for both hydrogen evolution reaction (HER) and UOR, with HER performances of -73 and -173 mV vs. RHE, and UOR performances of 1.32 and 1.37 V vs. RHE at 10 and 100 mA.cm-2, respectively. These UOR values were significantly lower than OER values. In a two-electrode system, the electrocatalyst exhibited cell voltages of 1.42 V at 10 mA.cm-2 and 1.71 V at 100 mA.cm-2. The preparation process enhanced electrochemical active surface area (ECSA), exposing more active sites. The catalyst showed remarkable durability in a 50-hour stability test at 100 mA.cm-2, with excellent mass transportability attributed to its porous structure. DFT calculations further validated the electronic coupling between Ni-Fe-Co LDH and Ni-S, highlighting the role of charge redistribution in optimizing catalytic activity. This work provides a cost-effective and scalable strategy for designing efficient bifunctional electrocatalysts for sustainable hydrogen production and urea-rich wastewater treatment.

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