A sandwiched Co-added polyoxometalate for efficient visible light-driven hydrogen evolution.

A new Co-added polyoxometalate (CoAP) Cs[(Co(HO)){(μ-Co(HO))Co(HO)(B-α-GeWO)}]·6HO (1) has been made using a lacunary directing strategy under hydrothermal conditions. Single-crystal X-ray diffraction analysis demonstrated that 1 is a one-dimensional (1D) chain, in which CoAP is linked by cobalt-oxygen octahedra to form a 1D structure with excellent chemical stability. The visible light-driven H evolution test demonstrated that 1 has high activity, with an H evolution rate of 1485.95 μmol h g. PXRD and FT-IR tests demonstrated that compound 1 exhibits excellent heterogeneous catalytic stability.