Two Co(II)/Ni(II) isostructural Metal-Organic Frameworks with bnn topology for photocatalysis and electrocatalysis

Two isostructural Co(II) and Ni(II)-based Metal-Organic Frameworks (MOFs), {[Co(bcpt)(bib)(3/2)(H2O)]center dot H2O}(n) (1), {[Ni(bcpt)(bib)(3/2)(H2O)]center dot H2O}(n) (2), have been synthesized and characterized (H(2)bcpt = 3,5-bis(3-carboxyphenyl)-1,2,4-triazole, bib = 1,4-bis(1-imidazoly)benzene). The mixed ligands linked metal ions to form a three dimensional 5-connected net with a rare bnn topology. Ni-MOF had the better degradation efficiency than CoMOF. They were carbonized in tube furnace at 800 degrees C and exhibited better HER activities than glass carbon: Co-MOF-800 with a lower onset potential (-210 mV); Ni-MOF-800 with a smaller Tafel slope (89.87 mV decade(-1)). We studied the HER activities for the mixture prepared from Co-MOF-800 and Ni-MOF-800, which aims to explore the role of metal ion.