In Situ Assembly of Recyclable Polyoxometalate-Derived Photocatalysts for Sustainable Photocatalytic H2 Generation

Polyoxometalate-derived photocatalysts with unique semiconductor-like performance and abundant catalytic sites are promising in photocatalysis. However, the cumbersome synthesis steps and complex structures of polyoxometalate-based compound carriers for photocatalysis pose significant challenges. In this study, we report two isostructural polyoxometalate-derived photocatalysts [M(H2O)4(TeMo6O24)][M(Hpca)(H2O)5]2 · 6H2O [M = Co (1), Zn (2)], in situ synthesized via iso-nicotinic acid (pca) as the organic ligand and Anderson-type polyoxometalate [TeMo6O24]6– as the inorganic block, which enable heterogeneous photocatalytic H2 production (3207.1 μmol g–1 h–1), far superior to most reported polyoxometalate-based heterogeneous systems. Moreover, compound 1, as a photocatalyst, displays excellent photocatalytic recyclability and stability. Density functional theory calculation reveals that the presence of the cobalt(II) ligand facilitates the H2 evolution reactions process, and the incorporation of M(Hpca)(H2O)5 further promotes the reaction. This work presents a versatile strategy for designing advanced polyoxometalate-based photocatalysts for sustainable photocatalytic H2 generation.