Cobalt metal-organic coordination polymer constructed from 2,3′-oxybisbenzoic acid and 1,3-di(pyridin-4-yl)propane: Crystal structure, slow magnetic relaxation and catalytic properties

Abstract

A new metal-organic coordination polymer, [Co(2,3′-oba)(dpp)]n (1) constructed from 2,3′-oxybisbenzoic acid (2,3′-H2oba) and 1,3-di(pyridin-4-yl)propane (dpp) was synthesized by hydrothermal method. The complex 1 is a 2D network structure connected by Co-2,3′-oba-Co-dpp helical chains. The temperature-dependent magnetic susceptibility and alternating current (ac) magnetic susceptibility measurements of the complex 1 were discussed. The complex 1 was shown to be a single-molecule magnet with slow magnetic relaxation behavior having an energy barrier Ueff of 15 ​K and τ0 =1.56 ​× ​10−6 ​s. As a catalyst, complex 1 exhibited excellent catalytic properties on the activation of peroxymonsulfate (PMS) for the dyes degradation. Specifically, an almost complete degradation of Rhb in aqueous solution was achieved by complex 1/PMS system with an efficiency of 99% within 15 ​min. The feasible active components were explored by quenching experiments, and the results showed that sulfate radicals generated in the degradation system was the main active constituent in the degradation process. The complex 1 has a highly stable skeleton structure which enabled its recycling in the dye degradation system. The obtained results provide an effective method for high degradation efficiencies of dyes in water.