Direct growth of ternary copper nickel cobalt oxide nanowires as binder-free electrode on carbon cloth for nonenzymatic glucose sensing

摘要

A new binder free electrode based on ternary copper nickel cobalt oxide nanowires grown on the carbon cloth (CuNiCoO4 NWs@ carbon cloth) was prepared and characterized by field emission scanning electron microscopy (FE-SEM), x-ray diffraction (XRD), Energy-dispersive X-ray spectroscopy (EDX), and cyclic voltammetry (CV). The prepared electrocatalyst was directly used for electrochemical sensing of glucose without using enzyme. The effect of different parameters such as potential scan rate, switching potential, and glucose concentration on the electrochemical oxidation of glucose was investigated. The results showed that such an electrode presents excellent catalytic activity toward the oxidation of glucose in aqueous alkaline solution. Under optimum conditions, the potential application of the electrode was evaluated by applying it to the analytical determination of glucose concentration. The results revealed that the electrocatalytic current increased linearly with the glucose concentration in the range from 0.02 to 1.4 mM with a low detection limit of 6.5 mu M and good sensitivity of as high as 1782 mu A mM(-1) cm(-2). Selectivity investigations demonstrate that the CuNiCoO4 NWs@CC electrode could be used for selective detection of glucose in the presence of interfering species. Real sample analysis shows reasonable RSD values implying negligible matrix effect in determination of glucose in human serum samples.