Turn Helical Motifs from Pair to Single Entangled Double Helixes in a Cobalt–Vanadate System via Introduction of a V-Shaped Ligand

Two novel helical compounds based on polyoxovanadates, [Co(H2O)2V2O6] (1) and [Co(bimb)V2O6] (2) (bimb = 1,3-bis(1-imidazoly)benzene), have been synthesized under identical hydrothermal conditions, providing two structurally different helical motifs due to introduction of a V-shaped bimb ligand in 2. Compound 1 possesses a pair of entanglement double helixes in a 3D inorganic framework, whereas compound 2 shows a single entangled double helix in a 3D inorganic-organic network owing to the influences of steric hindrance of ligands as well as coordination geometries of metal cations. The electrocatalytic and photocatalytic properties of 1 and 2 were also investigated in details.