Two Keggin-type arsenomolybdate organic-inorganic hybrid assemblies decorated by Cu-phen/bpy complexes for photo-/electro-catalytic performance

Two Keggin-type arsenomolybdate hybrids modified by Cu-phen/bpy complexes, [Cl{Cu-II(phen)(2)}(2)](2)]AsMo12O40](2)center dot H2O (1) and {{Cu-II(bpy)}{Cu-II(bPy)(2)}(2) (V-IV)(2)(AsMoVI (Mo7V4O40)-V-V-O-V)](2)center dot H2O (2) (phen = 1,10-phenanthroline, bpy = 2,2'- bipyridyl), were obtained by hydrothermal reaction and structurally characterized via routine techniques. In compound 1, two "butterfly"-shaped {Cu(phen)(2)} segments share a Cl bridge to form a unique binuclear complex unit {Cl(Cu(phen)(2))(2)}, which further interacts with six {AsMo12O40} clusters via hydrogen bond and other weak interactions yielding a 4,6-connected 3D network. The basic unit of 2 is a hepta-electron reduced tetra-V-substituted Keggin polyoxoanion {AsMoVI (Mo7V4O40)-V-V-O-V}, which is covered by two {(VO)-O-IV} cap on two trenches of {Mo4O18} group. Two {Cu-II(bpy)(2)} segments are connected with the {(VO)-O-IV} cap of the Keggin skeleton to form a bi-capped and bi-supported structure, which is further connected by {Cu-II(bpy)} linker leading to a covalent 1-D chains. The 3-D supramolecular network of 2 is formed by abundant hydrogen bonds and pi-pi interactions. Compounds 1 and 2 show effective photocatalytic performance for degradation of Azon Phloxine dyes under ultraviolet light irradiation and bifunctional electrocatalytic activity for reducing hydrogen peroxide and oxidizing ascorbic acid.