A 3-D porous structure of Ni-Fe-S nanosheets was created using a dynamic hydrogen bubble template (DHBT), which promotes active site exposure, on a nickel foam substrate as an efficient electrode for production hydrogen through electrochemical splitting assisted by urea oxidation reaction. In DHBT, high applied current densities result in the reduction of H+ ions alongside the Ni-Fe-S, forming H2. These H2 bubbles block the surface and force remaining ions to electrodeposit between the bubbles, resulting in a porous structure. The electrocatalyst exhibited remarkable performance for both the hydrogen evolution reaction (HER) and urea oxidation reaction (UOR). The parameters investigated in this study included applied current density, duration time, and FeSO4 concentration. The electrocatalyst synthesized at 5 A.cm-2, 10 s, and 0.1 M FeSO4 demonstrated highest catalytic activity, resulting in values of 85 and 173 mV vs. RHE for HER and 1.26 and 1.30 V vs. RHE for UOR to reach 10 and 100 mA.cm-2, respectively. In two electrode system of the Ni-Fe-S//Ni-Fe-S, it only requires a low voltage of 1.337 V vs. RHE to launch a current density of 10 mA.cm-2. The enhanced activity is thought to stem from the charge separation between the negatively charged S and the positively charged Ni and Fe, as well as the larger electrochemical active surface area (ECSA) and increased porosity. An insignificant shift in the potential was observed over a duration of 50 h at 100 mA.cm−2, indicating exceptional electrocatalytic stability for both HER and UOR. This study presents the impact of the utilization of UOR on enhancing the electrocatalytic performance of hydrogen production.

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