Abstract:
To achieve a carbon-neutral future, it is essential to develop sustainable methods for hydrogen
production by water electrolysis. Efficient and eco-friendly hydrogen production through
electrolysis demands significant energy input. This high energy requirement necessitates the
use of catalysts to reduce energy consumption making electrolysis process to be economically
viable. In this pursuit, we synthesized a bifunctional electrocatalyst (Fe3O4/NiO-C) with
improved catalytic performance using Ni-Fe-MOF as the precursor material. The Fe3O4/NiO
C catalyst demonstrated a substantial enhancement in electrochemical performance, faster
reaction kinetics, and long-term durability compared to pristine Ni-Fe-MOF. It achieved an
exceptionally high current density of 500 mA cm-2 at an overpotential of 280 mV for the oxygen
evolution reaction (OER) and 50 mA cm-2 at 182.5 mV for the hydrogen evolution reaction
(HER), with Tafel slopes of 59.0 mV/dec and 53 mV/dec, respectively. Additionally, it showed
extended electrochemical stability, maintaining 86% performance for OER and 93% for HER
after 24 hours of chronoamperometry test. The outstanding performance of Fe3O4/NiO-C is due
to its unique composition, interfacial interactions, and its high surface area and porosity. This
research emphasizes the significance of MOF-derived transition metal oxides as highly
efficient, active, and stable bifunctional electrocatalysts for water-splitting.
