Scalable synthesis of transition metal sulfides with Turing- pattern-like structure for efficient and robust oxygen evolution electrocatalysis

The scalable fabrication of transition metal sulfide (TMS) electrodes with both high electrocatalytic activity and structural robustness remains a significant challenge for the electrocatalytic oxygen evolution reaction. Here, we report a non-equilibrium spray pyrolysis strategy that exploits the rapid decomposition of thiourea to synthesize meter-scale (1.2 × 0.5 m 2 ) Turing-pattern-like TMS electrodes. Concurrent sulfurization of the substrate induces in situ -generated reactive metal–sulfur interfaces, which yield strong catalyst-substrate adhesion. As a representative example, the synthesized Ni 0.75 Fe 0.25 S 2−δ delivers a current density of 1 A cm −2 at a cell voltage of 1.71 V when employed as the anode in an anion exchange membrane water electrolyzer, and sustains operation for 5000 h with limited degradation. The Turing-pattern-like structure increases active site exposure and promotes efficient mass transport. Complementary density functional theory calculations and in situ spectroscopic analyses reveal that sulfur vacancies facilitate the formation of electrochemically active oxyhydroxide species. This work establishes a versatile strategy for designing advanced electrocatalysts through the synergy of interfacial reinforcement and microstructural engineering, offering a promising pathway toward industrial-scale water electrolysis.