Rational design of two novel metal-organic frameworks as photocatalysts for degradation of organic dyes and their derived materials as electrocatalysts for OER

Abstract Metal-organic framework (MOFs) and their derivatives have received numerous attention of potential applications for electro/photo-catalysis because of their diverse structures and tunable properties. In this study, two novel cobalt-based MOFs [Co4(bbibp)5(HCOO)8(H2O)2]n (compound 1) and [Co(bimmb)(NO3)2]n (compound 2) were constructed by selecting different N-donor bridging ligands (bbibp = 4,4-bis(imidazol-1-yl)biphenyl, bimmb = 1,4-bis(imidazol-1-ylmethyl)benzene). The structures of two compounds were well characterized by single crystal X-ray diffraction. The photocatalytic degradation of two compounds were investigated, which showed both of two compounds have good photocatalytic activities for MB. Moreover, a carbon-based cobalt oxide nanoparticle (CoO@C-1) was prepared using compound 1 as a precursor and used for electrocatalytic OER. The result indicated that CoO@C-1 has good electrocatalytic activity with a small overpotential of 377 mV at 10 mA cm−2 and smaller Tafel slope of 70 mV dec−1.