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

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 enzymebased 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 mu A mM- 1 cm- 2, a fast response time of 1.36 s, and a low detection limit of 1.1 mu M. 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.