A sandwiched Co4-added polyoxometalate for efficient visible light-driven hydrogen evolution

Abstract

A new Co₄-added polyoxometalate (CoAP) Cs₄[(Co(H₂O)₅)₂{(μ₂-Co(H₂O)₄)₂Co₄(H₂O)₂(B-α-GeW₉O₃₄)₂}]·6H₂O (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 H₂ evolution test demonstrated that 1 has high activity, with an H₂ evolution rate of 1485.95 μmol h⁻¹ g⁻¹. PXRD and FT-IR tests demonstrated that compound 1 exhibits excellent heterogeneous catalytic stability.