Hollow carbon spheres with a controllable shell structure

In this work, hollow carbon spheres (HCSs) with smooth single shells, deformed single shells, double shells, and N-doped shells were prepared using silica spheres as templates and benzene as a carbon precursor via chemical vapor deposition (CVD). It was observed that the morphology of the HCSs largely depended on the experimental conditions, including CVD duration and temperature, and the diameter of silica spheres. Results showed that relatively large silica spheres favored the formation of HCSs with a very smooth surface. A short CVD time led to a thin carbon shell, thus deformed HCSs. High CVD temperatures enhanced the graphitic nature of the HCSs. Experimental data also demonstrated that the cyclability of the HCSs as an anode in lithium-ion batteries was improved after doping with N. The use of HCSs as templates for the fabrication of monodisperse hollow silica spheres was also demonstrated in this work.