Two 3D POM‐Based Inorganic–organic Hybrid Compounds Constructed from Different {VO₃}_4n Subunits and N‐donor ligands: Syntheses, Structures, Electrocatalytic and Magnetic Properties

Abstract

Two new 3D organic‐inorganic hybrid materials Cu(bim)V2O6 (1) (bim=bis(1‐imidazolyl)methane) and Co(2‐mbim)V2O6 (2) (2‐mbim=bis(2‐methylimidazol‐1‐yl)methane) based on polyoxovanadates (POVs) and organic ligands decorated transition metal units have been synthesized by solvothermal methods. Single crystal XRD, soild UV‐vis and IR spectra, powder XRD, magnetic measurement and thermogravimetric (TG) measurements were performed to analyze the structures and properties of 1 and 2. The topological structures of both compounds are interesting, and not reported previously. Structural analysis indicates that compound 1 features a 3D zeolite‐like framework, constructed by wave‐like {V4O12}n4n− chains and [Cu(bim)2]n2n+ chains. These parallel chains constitute the fundamental motif via ‐(Cu‐O−V)‐ helical bridges. In the structure of 2, {V4O12}4− cycle is linked with four {V4O12}4− cycles giving rise to 2D {Co2V4O12}n layers which were further pillared by the organic 2‐mbim ligand via N–Co–O linkages to form the 3D framework. Electrochemical studies exhibit that compound 1 possesses excellent electrocatalytic activity toward the reduction of hydrogen peroxide. The magnetic susceptibility measurement indicates antiferromagnetic interactions in both 1 and 2.