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

Abstract 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 (ReS 2 ) on carbon cloth (NC‐CoNi 2 S 4 @ReS 2 /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‐CoNi 2 S 4 @ReS 2 /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‐CoNi 2 S 4 @ReS 2 /CC presents exceptional electrocatalytic activity in both alkaline water/seawater electrolytes. Stability assessments reveal that NC‐CoNi 2 S 4 @ReS 2 /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.