Syntheses, Crystal Structure, Characterization, and Properties of Two Novel Superamolecular Phosphotungstate-Pyridine Complexes

Two new inorganic-organic compounds constructed from phosphotungstate and pyridines have been synthesized under hydrothermal conditions. The formulas of the two compounds are (C5H7N2)3(C5H6N2)3(PW12O40)·2H2O (1) and (C6H8N)3(C6H7N)(PW12O40)·9H2O (2). They have been characterized by IR, UV-vis, TG-DTA, FL, CV, and single-crystal X-ray diffraction. The two compounds both show three-dimensional networks. These compounds exhibit good catalytic activity for catalytic oxidation of methanol over a continuous-flow fixed-bed microreactor, when the initial concentration of methanol is 5.37 g⋅m−3, and flow rate is 4.51 mL⋅min−1. 0.2 g compound 1 (or compound 2) as the catalyst can eliminate methanol completely at 150°C (175°C for compound 2).