Nonenzymatic electrochemical sensor based on Fe@Pt core–shell nanoparticles for hydrogen peroxide, glucose and formaldehyde

Fe@Pt core–shell nanoparticles were synthetized by spontaneous replacement reaction, using Vulcan XC-72 carbon as support. The physical properties of the obtained Fe@Pt/C nanocomposites were characterized by X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy, and the electrocatalytic performances of the Fe@Pt/C were evaluated by cyclic voltammetry and chronoamperometry . Compared with the Pt/C, the Fe@Pt/C exhibited preferable electrocatalytic activity towards the reduction of hydrogen peroxide, and the oxidation of glucose and formaldehyde. Amperometric sensing of hydrogen peroxide was linear to its concentration in the range from 2.5   μM to 41.605   mM, with a detection limit of 750   nM (S/N   =   3) and a sensitivity of 218.97   μA mM −1 cm −2 . At the same time, the sensor based on Fe@Pt/C showed a linear response range of 1–16   mM glucose, and of 12.5   μM–15.4   mM formaldehyde, with high sensitivities of 11.75   μA mM −1 cm −2 and 40.18   μA mM −1 cm −2 , respectively.