Three hybrid networks based on octamolybdate: ionothermal synthesis, structure and photocatalytic properties

Three hybrid networks based on octamolybdate building units, Cu(I)(8)BBTZ(6)[(α-Mo(8)O(26))(β-Mo(8)O(26))] (1), (Cu(I)BBTZ)(4)[Mo(7)Cu(II)O(24)(H(2)O)(2)]·6H(2)O (2), and Cu(II)Cu(I)(2)BBTZ(5)[β-Mo(8)O(26)] (3) (BBTZ = 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene), have been synthesized under ionothermal conditions and structurally characterized by single-crystal X-ray diffraction. 1 exhibits a rare 3D three-fold self-penetration network (SPN) structure, in which the interpenetrating polymer networks (IPN) formed by α-Mo(8)O(26) units, Cu(I) ions and BBTZ ligands are united by β-Mo(8)O(26) units. 2 shows a classic 10(3)-utp net built by transition-metal monosubstitution octamolybdate β-Mo(7)CuO(26), Cu(I) and BBTZ ligands. 3 displays an interesting interpenetrating network (IPN) structure formed by 2D poly-rings layers and 3D NaCl topology framework. IR, TG, and electrochemical studies were also conducted to further authenticate the identities of these compounds. Photocatalytic investigation indicates that compounds 1-3 are active for photocatalytic H(2) evolution under UV irradiation.