Synthesis of Heteroatom-Doped Hollow Mesoporous Carbon Nanospheres for Lithium-Sulfur Battery and Supercapacitor Applications

초록

Nitrogen (N), fluorine (F)-doped hollow mesoporous carbon nanospheres (denoted as NF-HMCs) are prepared based on the template of silica core/mesoporous silica shell nanospheres. These nanospheres possess a large surfac area and well-defined pore structure. They were impregnated with sulfur through a melt-diffusion method to be fabricated to prepare the cathode for lithium-sulfur (Li-S) battery applications. The cathode fabricated with NF-HMCs delivered a high reversible capacity and coulombic efficiency (623.7 mAg/g, 99.7% at 0.2C after 200 cycles). Simultaneously, the F-doped hollow mesoporous carbon nanospheres (F-HMCs) having a large surface area and well-defined pore structure were prepared based on the template of a crosslinked PS-core with a mesoporous silica shell, F-HMCs were also fabricated into an electrode in the supercapacitor applications. The capacitance value measured after 10,000 cycles was about 162.8 F/g at 1 A/g and maintained about 93.6% of the initial value.