Reconstruction Induced Dynamic Incorporation of Zn Into Cobalt Hydroxide via Synergistic Structural Evolution for Efficient Hydrogen Evolution Reaction

Surface reconstruction of electrocatalysts induces structural evolution, which critically creates favorable conditions for in situ directional modulation of electrocatalytic species and thus enhances the catalytic activity. The development of CoMoO₄-based electrocatalysts for hydrogen evolution reaction (HER) is hindered by insufficient active sites and sluggish reaction kinetics of reconstructed cobalt species. Herein, we rationally designed a CoMoO₄ pre-catalyst loaded on ZnO nanorods, where synergistic structural evolution between ZnO and CoMoO₄ is achieved: continuous ZnO dissolution couples with CoMoO₄ structural evolution, driving Zn incorporation into in-situ generated Co(OH)₂ species. The reconstructed electrocatalyst with Zn-doped Co(OH)₂ as catalytic species can exhibit a low HER overpotential of 40 mV at 10 mA cm^{- 2}, and maintain an overpotential of 65 mV at 10 mA cm^{- 2} in simulative seawater electrolyte. Meanwhile, the anion exchange membrane (AEM) electrolyzer with the reconstructed ZnO@CoMoO₄ electrode can exhibit excellent durability, maintaining electrocatalytic performance for 650 h (water electrolysis) and 1000 h (seawater electrolysis). Density functional theoretical (DFT) calculations demonstrate that the Zn dopants in the reconstructed species effectively enhance the HER energetics and mitigate Cl^--induced corrosion during the seawater electrolysis. This work provides fresh insights into the enhancement of the HER activity of reconstructed electrocatalysts based on the structural co-evolution mechanism.