Facile design and synthesis of ultrafine FeCo nanocrystallines coupled with porous carbon nanosheets as high efficiency non-enzymatic glucose sensor

A series of FeCo alloy nanoparticles coupled with porous carbon nanosheets (denoted as FeCo@PCNSs-T) are successfully synthesized by calcining the three dimensional (3D) porous precursor networks (prepared by electrospinning technique) at different pyrolysis temperatures. The glucose oxidation and detection performances of the resultant FeCo@PCNSs-T catalysts decrease in the order of FeCo@PCNSs-800 > FeCo@PCNSs-700 > FeCo@PCNSs-900 > FeCo@PCNSs-1000 > FeCo@PCNSs-600. The experimental results prove that the optimal FeCo@PCNSs-800 catalyst exhibits a rapid response time (3.0 s), large sensitivity values (1766.5 mA cm(-2) mM(-1) between 0.005 and 1.70 mM and 826.7 mu A cm(-2) mM(-1) between 1.70 and 13.60 mM), a low detection limit (0.1 mu M), excellent anti-interference to electroactive molecules and Cl-, a perfect reproducibility and a superior long-term stability for glucose sensor. The structural and chemical components of the resultant FeCo@PCNSs-T catalysts are analyzed by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, N-2 adsorption-desorption and X-ray photoelectron diffraction techniques. On the basis of the resultant experimental results, we can confirm the major factors of an excellent glucose sensor efficiency of the FeCo@PCNSs-800: (1) the FeCo alloy nanoparticles coupled with PCNSs can enhance the conductivity of composite. (2) The Fe elements in FeCo alloy nanoparticles can increase the number of active Co-IV sites. (3) The 3D hierarchically porous architectures afford a large surface area for dispersing more ultrafine FeCo nanoparticles, which can obviously increase the number of CoIV sites. (4) The meso/macroporous channels can effectively decrease the mass transport resistances. Furthermore, the FeCo@PCNSs-800 catalyst also exhibits a satisfying efficiency for glucose detection in human serum samples. (C) 2019 Elsevier B.V. All rights reserved.