| Porous carbon materials display potential applications in catalysis, fuel cell, storage adsorption, seperation and hydrogen duo to their structural properties such as high surface, controllable pore size and good conductivity. The establishement of the correlation between the structure and the functionalization of the porous carbon remains a especially interesting topic in catalysis and. materials sciences.In this paper, near-monodisperse polyaniline (PANI) colloids with controlled particle size (55-90 nm) were prepared by disperse polymerization of aniline in the presence of a steric stabilizer of polyvinylpyrrolidone (PVP). The nitrogen-doped carbon shells (NCSs) were fabricated by pyrolyzing silica-coated PANI colloids at different temperatures (400?950oC). The physical/chemical properties of various NCSs and Pt/NCSs were characterized by N2 adsorption, X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), elemental analysis, and thermogravimetic analysis (TGA).The obtained NCSs remained themesoporous shells by pyrolysis treatment at different temperatures (400?950 oC). The resultant NCSs exhibited large surface area (115-670 m2/g) and large mesopore (13.4-23.2nm). The FTIR spectrum and elemental analysis showed that the amount of N on the surface of carbon was decreased with the increase of the pyrolysis temperature. XPS suggested that nitrogen atoms were existence in graphitic sheets as pyridine-like and quaternary nitrogen.The Pt catalyst supported on NCS synthesized at different temperatures. The electrocatalytic performances of various Pt/NCS electrodecatalysts during electro chemical methanoloxidation were investigated by cyclic voltammetric. It was found that the Pt catalyst supported on NCSs exhibited uniformly small particles size and improved CO tolerance. The activity of Pt/NCS-950 is 1.3 times higher than that of Pt/Vulcan XC-72 in term of methanol oxidation under otherwise the identical experiment conditions. |
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