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.