Versatile bimetallic metal-organic framework with nanocutting channels tailored for efficient electrocatalytic water oxidation and glucose detection

Metal-organic frameworks (MOF) with outstanding properties have shown great potential for electrochemical water splitting, particularly for the oxygen evolution reaction (OER) and nonenzymatic glucose detection. In this study, a facile method was used to synthesize CoNiMOF (with 5-aminoisophthalic acid as the organic linker) as electrocatalyst for the OER and glucose oxidation reaction (GOR). In-depth structural and microstructural analyses confirmed the formation of the MOF via metal-ligand (electron donor-acceptor) coordination. Among the different CoNiMOFs, CoNi(1:3)MOF shown to have nanocutting channels along the edges of the microstructural sheets, exhibited good catalytic activity toward the OER and GOR. CoNi(1:3)MOF delivers the best electro-catalytic performance in 1 M KOH with an overpotential of 348 mV at 20 mA cm-2 for the OER, benefitting from the specific morphology and electronic control. Moreover, the electrocatalyst was remarkably stable after 5000 cyclic voltammetry cycles and chronopotentiometric (20 h) analysis. As glucose sensor, CoNi(1:3)MOF exhibits a remarkably low glucose detection limit (1.03 mu\M) and wide detection range (2-500 mu\M and 1-15 mM, respectively). In addition, CoNi(1:3)MOF performed efficiently in an interference study, which revealed the selectivity of the developed sensor. The active formation of bimetallic MOF structures and the synergistic effect between the two metals in the electrocatalyst is attributed to the efficient modulation of the electronic structure, which effectively influenced the OER and GOR performance.