• • The activated Cu/Co/Co(OH)2/MX catalyst delivers an overpotential of −78 mV at 10 mA cm−2 for HzOR, with a Tafel slope of 28.7 mV dec−1, enabling a two-electrode electrolyzer to achieve 100 mA cm−2 at a cell voltage of 0.252 V—a 1.519 V reduction relative to conventional water electrolysis, which directly translates to lower operational costs for industrial hydrogen generation.
• • Theoretical calculations show that Cu incorporation lowers the Co d-band center from −0.867 to −0.883 eV, weakening intermediate adsorption and reducing the free energy barrier of the rate-determining step from 0.33 to 0.24 eV; this 27% barrier reduction is critical for sustaining high current densities without excessive potential penalties.
• • The in-situ electrochemical reduction strategy reconstructs Co(OH)2 to a metallic Co/Co(OH)2 interface, as evidenced by the formation of Cu/Co/Co(OH)2/MX; this reconstruction enhances electron transfer and creates active sites that remain stable under operating potentials, addressing the durability limitations of conventional OER catalysts.
• • The bifunctional catalyst operates in a two-electrode configuration with a cell voltage of only 0.252 V at 100 mA cm−2, compared to ~1.77 V for water electrolysis; this 87% voltage reduction implies that hydrazine-assisted hydrogen production could achieve cost parity with steam methane reforming when coupled with renewable electricity, provided hydrazine supply and safety protocols are managed.