The nickel phosphate rods derived from Ni-MOF with enhanced electrochemical activity for non-enzymatic glucose sensing

In this work, spherical Ni-based metal-organic frameworks (Ni-MOFs) were used as precursors for preparing nanorod-like nickel phosphate (r-NiPO) with enhanced electro-catalytic properties in detection of glucose. It was found that the addition of nickel ion has a profound effect on construction of nickel phosphate with flower-like, rod-like, and ribbon-like structure in presence of H2PO2-. The r-NiPO consisted of multiple phases of nickel phosphate showed porous, interconnected structure and abundant active Ni(II)/Ni(III) pairs, which was beneficial to facilitate glucose oxidation. In comparison with Ni-MOF, r-NiPO exhibited the superior electrocatalytic property on oxidation of glucose because of the exposing more active Ni sites in r-NiPO than that of Ni-MOF precursor. r-NiPO modified glassy carbon electrode (r-NiPO/GCE) showed a good linear response to glucose from 1.0 μM to 3.0 mM with a high sensitivity of 3169 μA mM-1 cm-2. In addition, r-NiPO/GCE can be used to detect glucose in human serum with satisfactory recoveries (90-97%).