Solvothermal Synthesis, Crystal Structure, and Photocatalytic H2 Evolution of two CuII Coordination Polymers Based on Keggin Polyoxotungstates†

Two new CuII coordination polymers based on α-Keggin polyoxotungstates, [Cu2(dpa)2(H2O)2(GeW12O40)]·0.5CH3COOH (1) and [Hdpa][Cu2(dpa)2(4,4′-bipy)(H2O)2(PW10V2O40)] (2) (dpa = 2,2′-dipyridylamine, 4,4′-bipy = 4,4′-bipyridine), were obtained by solvothermal reactions in glacial acetic acid and characterized by elemental analysis, IR spectroscopy, TG analysis, X-ray powder diffraction, and single-crystal X-ray diffraction. Compound 1 exhibits a 1D two-rowed chain constructed from [GeW12O40]4– anions coordinated with [Cu(1)(dpa)]2+ and [Cu(2)(dpa)(H2O)2]2+ fragments by four terminal oxygen atoms. Compound 2 exhibits a 2D layered structure constructed from [PW10V2O40]5– anions coordinated with [Cu(dpa)(4,4′-bipy)0.5(H2O)]2+ fragments by four terminal oxygen atoms. Furthermore, the electrochemical properties of 1 and the photocatalytic hydrogen production of 1 and 2 were investigated.