Interface-Driven Catalytic Enhancements in Nitrogen-Doped Carbon Immobilized CoNi₂S₄@ReS₂/CC Heterostructures for Optimized Hydrogen and Oxygen Evolution in Alkaline Seawater-Splitting

The rational design of multicomponent heterostructure is an effective strategy to enhance the catalytic activity of electrocatalysts for water and seawater electrolysis in alkaline conditions. Herein, MOF-derived nitrogen-doped carbon/nickel-cobalt sulfides coupled vertically aligned Rhenium disulfide (ReS₂) on carbon cloth (NC-CoNi₂S₄@ReS₂/CC) are constructed via hydrothermal and activation approaches. Experimental and theoretical analysis demonstrates that the strong interactions between multiple interfaces promote electron redistribution and facilitate water dissociation, thereby optimizing *H adsorption energy for the hydrogen evolution reaction (HER). Meanwhile, the adsorption energies of oxygenated intermediates are balanced to reduce the thermodynamic barrier for the oxygen evolution reaction (OER). Consequently, NC-CoNi₂S₄@ReS₂/CC shows smaller overpotentials of 87 and 253 mV for HER and OER at 10 mA cm⁻², with a lower Tafel slope and R_ct than control samples. Superior catalytic stability is confirmed by cyclic voltammetry (CV) for 1000 cycles and CA test for 56 h. Furthermore, NC-CoNi₂S₄@ReS₂/CC presents exceptional electrocatalytic activity in both alkaline water/seawater electrolytes. Stability assessments reveal that NC-CoNi₂S₄@ReS₂/CC maintains a highly catalytic activity in both water and seawater, owing to the corrosion-resistant properties of the sulfur species at the interface. These findings highlight the importance of designing heterostructure electrocatalysts for clean hydrogen production.