Nano-architectures of ordered hollow carbon spheres filled with carbon webs by template-free controllable synthesis.

Hollow carbon spheres with a carbon network structure inside have been synthesized in the absence of templates for the first time. The samples were characterized by scanning electron microscopy, transmission electron microscopy, x-ray diffraction, N(2) adsorption-desorption, and thermogravimetric analyses. The experimental results indicate that the core and the shell of this new structure contain both mesopores and micropores. Furthermore, the inner space and thickness of the hollow carbon spheres can be controlled by adjusting the molar ratio of the glucose and Na(2)SnO(3)·H(2)O. Moreover, a possible formation mechanism has been suggested on the basis of time-dependent experiments. The electrocatalytic activity of methanol oxidation on Pt supported on HC electrocatalyst (Pt/HC@C) is 1.8 times higher than that of Pt supported on commercial Vulcan XC-72 carbon (Pt/C) electrocatalyst at the same Pt loadings.