One step synthesis of hierarchical Cu nanoparticles-Co(OH)2 nanoflakes/Nifoam electrode for ultrasensitive detection of glucose

Abstract Co(OH) 2 nanoflakes integrating with Cu nanoparticles were deposited on nickel foam (CuNps-Co(OH) 2 Nfs/Ni f ) by a green and facile one-step deposition method and used for non-enzymatic glucose sensors. The CuNps-Co(OH) 2 Nfs/Ni f composite was characterized by scanning electron microscopy, X-ray photoelectron spectroscopy and high resolution transmission electron microscopy. Electrochemical oxidation of glucose on the CuNps-Co(OH) 2 Nfs/Ni f composite was investigated by chronoamperometry and cyclic voltammetry. The prepared CuNps-Co(OH) 2 Nfs/Ni f electrode shows not only an extremely high sensitivity of 42.7 mA mM −1  cm −2 in the concentration range from 1 to 250 μM for glucose detection but also an obvious current response to glucose at a level of 1 μM with a low detection limit of 73 nM (S/N = 3). Moreover, the glucose sensor based on CuNps-Co(OH) 2 Nfs/Ni f also exhibits high recovery ratio toward real sample analysis. This work indicates that the fast electron transfer, large surface area, and highly effective active sites based on the hierarchical structure of ultra-thin and open-interlaced Co(OH) 2 Nfs interspersed by CuNps contribute to the excellent performance of CuNps-Co(OH) 2 Nfs/Ni f electrodes. The proposed one-step preparation of hierarchical nanostructure of CuNps and Co(OH) 2 Nfs provides a promising and efficient strategy in the development of outstanding non-enzymatic glucose biosensors.