Hierarchical Co₉S₈/ZnIn₂S₄ Nanoflower Enables Enhanced Hydrogen Evolution\nPhotocatalysis

Abstract

Photocatalytic\nwater splitting with clean solar energy is a sustainable\nway to produce green hydrogen (H₂) fuel. Here, an efficient,\nvisible-light-responsive hierarchical Co₉S₈/ZnIn₂S₄ photocatalyst is designed by decorating Co₉S₈ nanoparticles on ZnIn₂S₄ nanoflower through a two-step solvothermal process for photocatalytic\nH₂ evolution. Two photoactive sulfide–sulfide integrations\nin a stable, hierarchical, and flower-like Co₉S₈/ZnIn₂S₄ heterojunction, provide large surface\nareas with rich active centers and endow a quick separation and transfer\nof photoinduced electrons and holes. With the optimal loading amount\nof Co₉S₈, the Co₉S₈/ZnIn₂S₄ photocatalyst, under visible-light illumination,\nfree of any cocatalysts, reaches a high hydrogen evolution rate of\n126.7 μmol h^–1 or 12.67 mmol h^–1 g^–1 with high stability, which is 6 times higher\nthan that of individual ZnIn₂S₄. Our effort\nmay give some inspirations to the delicate design of competent novel\nstructured photocatalysts for reinforcing photocatalytic performance.