Synthesis of nickel(ii) coordination polymers and conversion into porous NiO nanorods with excellent electrocatalytic performance for glucose detection

Abstract

A nanostructured nickel–salicylic acid (SA) coordination polymer, Ni(SA)₂(H₂O)₄ has been successfully synthesized under hydrothermal conditions on a large scale without the assistance of surfactants or template. After heat treatment, the Ni(SA)₂(H₂O)₄ coordination polymers were converted into NiO nanostructures. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) results showed that the length of the as-prepared NiO varies from 2.0 to 3.0 μm with an average diameter of 150 nm. Due to a large number of gases released during thermal decomposition, the obtained NiO is formed of porous nanostructures. The porous NiO was used as an electrocatalyst for the detection of glucose in a nonenzymatic electrochemical sensor. The porous NiO modified glassy carbon (p-NiO/GC) electrode shows a wide linear range (0.01–5 mM), a low detection limit (2 μM), and a high sensitivity (364 μA mM⁻¹ cm⁻²), as well as good stability and reproducibility. More importantly, the common interfering species, such as ascorbic acid (AA), uric acid (UA), and 3,4-dihydroxyphenylacetic acid (DOPAC) did not cause any interference at the detection potential (0.45 V vs. SCE). Furthermore, the nonenzymatic sensor was successfully applied to the determination of the glucose concentration in human serum samples.