Metal(II) complexes synthesized based on quinoline-2,3-dicarboxylate as electrocatalysts for the degradation of methyl orange

Based on quinoline-2,3-dicarboxylic acid (H2L), two metal(II) complexes formulated as MnL(phen)(H2O)center dot H2O (phen = 1,10-phenanthroline) (1) and Co(HL)(2)(PPA)center dot 4H(2)O (PPA = N-1,N-4-di(pyridin-4-yl)terephthalamide) (2) were synthesized and structurally characterized by single-crystal X-ray diffraction. Both complexes 1 and 2 exhibit one-dimensional (1D) chain-like structures, in which stable five-membered rings are observed. Different chains are linked by strong pi-pi stacking interactions into a three-dimensional (3D) supramolecular architecture. Both complexes can increase the degradation rate of methyl orange (MO), which is expected to be associated with their electrocatalytic activities for the H-2 evolution reaction from water.