Two novel Co(II) coordination polymers based on 1,4-bis(3-pyridylaminomethyl)benzene as electrocatalysts for oxygen evolution from water

Based on the L (1,4-bis(3-pyridylaminomethyl) benzene) ligand, two MOFs formulated as Co(L)(0.5)(adip) (H(2)adip = adipic acid) (1) and Co-2(L)(2)(5-bdc)(2)(H2O)(2)center dot H2O (2) (5-H(2)bdc = 5-nitroisophthalic acid) (2) were synthesized and structurally characterized by single-crystal X-ray diffraction. Complex 1 features a uninodal 4-connected non-interpenetrated sql/Shubnikov tetragonal plane net with {4(4).6(2)} topology. In complex 2, two L link two Co(II) centers into a quadrangular cage, and different cages are further connected by two strands of 5-bdc(2-) into a 1D chain. The two complexes both exhibit electrocatalytic activities toward generating O-2 from water with lowered overpotentials and enhanced currents, and they show different UV-vis absorption spectra and thermal stabilities.