Controlled synthesis of Ni nanoparticles embedded within N-doped carbon nanotubes for electrochemical nonenzymatic glucose sensing

Abstract

Constructing a cost-effective glucose sensor has attracted the attention of researchers, since the detection of blood glucose level play a critical role on determining diabetes. The electrochemical nonenzymatic glucose sensor has the advantages of good stability, high sensitivity and low fabrication cost, compared with enzyme-based glucose sensors. Herein, the Ni nanoparticles embedded within N-doped carbon nanotubes was prepared by high-temperature pyrolysis of precursor composed of NiCl₂ and dicyandiamide, namely Ni@NC₇₀₀. Benefiting from the abundant Ni³⁺ active species from electrooxidation of Ni nanoparticles and the large specific surface area and electrical conductivity of Ni@NC₇₀₀, the nonenzymatic sensor presented a remarkable electrocatalytic glucose oxidation performance. The resulting Ni@NC₇₀₀ exhibited a high sensitivity of 299.65 μA mM⁻¹ cm⁻², a fast response time of 1.36 s, and a low detection limit of 1.1 µM. In addition, the Ni@NC₇₀₀ showed the excellent anti-interference ability in the presence of dopamine, KCl, urea, NaCl, uric acid, ascorbic acid, sucrose, and maltose interferences. In addition, the sensor exhibited good stability and satisfactory reproducibility (RSD of 1 %). The successful synthesis of the Ni nanoparticles embedded within N-doped carbon nanotubes provided intensive insight on high-efficiency electrochemical nonenzymatic glucose sensing.