Construction of core-shell structured nickel@platinum nanoparticles on graphene sheets for electrochemical determination of nitrite in drinking water samples

摘要

Core-shell structured Ni@Pt nanoparticles were fabricated on graphene [Ni@Pt/Gr] using ethylene glycol during the reduction step. X-ray diffraction (XRD), transmission electron microscopy (TEM) and electrochemical studies were applied to characterize this synthesized nanocomposite. Ni@Pt/Gr electrode demonstrated an enhanced electrocatalytic activity towards nitrite determination in relation to that at Pt/Gr. The catalytic rate constant value at Ni@Pt/Gr electrode was 1.92 times higher than that at Pt/Gr. Linear calibration curves were measured at Pt/Gr and Ni@Pt/Gr electrodes in nitrite concentration range of 10 mu M-15 mM. The corresponding sensitivity values of Pt/Gr and Ni@Pt/Gr electrodes were 33.04 and 85.18 mu A mM(-1) cm(-2). The prepared nanocomposite could successfully estimate nitrite concentration in drinking water samples.