Ni-MOF derived rod-like nickel hydroxide through controllable hydrolysis for efficient electrocatalytic glucose oxidation

Abstract

In this work, a new rod-like Ni-MOF (rNi-MOF) acted initially as an important catalyst in hydrolyzing of extrinsic Ni2+. Then rNi-MOF would also be etched by protons (the other product of hydrolysis) resulted in increasing free Ni2+ that can bond with OH− for in-situ formation of Ni(OH)2 coated on rNi-MOF. The amount of extrinsic Ni2+ and water showed significant influences on morphology of rNi-MOF/Ni(OH)2. It was found the rNi-MOF/Ni(OH)2 prepared by 4 mL water and 0.5 mmol Ni2+ exhibited excellent electrochemical performances in detection of glucose due to its high specific surface area (220 m2 g−1), abundant active Ni(II)/Ni(III) pairs. The rNi-MOF/Ni(OH)2 modified glassy carbon electrode (rNi-MOF/Ni(OH)2/GCE) exhibited a high sensitivity of 3616 μA mM−1 cm−2, the low detection of limit (0.7 μM). Moreover, the proposed modified sensor displayed a high reproducibility and stability which set a foundation for promising application in detecting of glucose in human serum with good recoveries (95 %–105 %).