▎ 摘　　要

Two polymolybdate-based complexes formulated as (H(2)L1)(2)(Mo4O13) (1) and (L2)(2)(HL2)(2)(Mo8O25)center dot 7H(2)O (2) have been hydrothermal synthesized and structurally characterized by single-crystal X-ray diffraction. In complex 1, one-dimensional (1D) [(Mo4Mo4O26)-Mo-V-O-VI](infinity)(8-) chain is constructed by vertice-sharing {MoO6} octahedra, and the uncoordinated protonated [H(2)L1](2+) species link different [Mo8O26](infinity)(8-) chains via supramolecular forces. In complex 2, the [Mo8O25](2-) moieties are linked by the mu(3)-[HL2](+) and mu(2)-L2 ligands into 1D chain. Complex 2 possesses more narrow band gap than complex 1, and it shows stronger photocurrent response than complex 1 under the visible light (650 nm > lambda > 350 nm). The different densities of states (DOS) of the two complexes are attributed to their different compositions and frameworks, thus giving rise to their different band gaps. With the addition of graphene into the two complexes, the electroconductivity of the complex/graphene composite material is much improved, and 2/graphene composite material shows much improved electrocatalytic activity for the H-2 evolution reaction (HER) than complex 2.