中文摘要：

以炭黑为原料,硝酸铁为催化剂前驱体,氮气气氛下1000℃高温炭化制备了直径为40nm的中空洋葱状碳纳米颗粒（OC）.用SnCl2/乙醇溶液浸渍,空气中350℃氧化得到SnO2/OC复合材料.进一步对该复合材料进行酸处理制备OC包覆的SnO2电极材料.采用X射线衍射（XRD）、扫描电镜（SEM）、透射电镜（TEM）和热失重分析（TGA）对OC和SnO2/OC复合材料进行表征;利用恒电流充放电和循环伏安（CV）方法对复合材料作为锂离子电池负极材料的电化学性能进行表征.结果表明：酸处理后的复合材料的循环性能得到明显改善,50次循环后可逆容量保持为446mAh·g^-1,OC起到了缓冲SnO2膨胀和阻止团聚的作用.

英文摘要：

New kinds of onion-like hollow carbon nanoparticles（OC） with a mean diameter of 40 nm were synthesized by the pyrolysis of carbon black at 1000 ℃ in a nitrogen atmosphere using ferric nitrate as the catalyst precursor.By impregnating with a SnCl2/ethanol solution and oxidation in air at 350 ℃,OC doped SnO2 nanoparticle composites were obtained.Then,by rinsing with hydrochloric acid to remove the coated SnO2 nanoparticles,OC-encapsulated SnO2 nanoparticle composites were prepared.The morphologies and structures of OC and the composites were characterized by X-ray diffraction（XRD）,scanning electron microscopy（SEM）,and transmission electron microscopy（TEM）.The content of SnO2 in the composite was measured by thermogravimetric analysis（TGA）.The electrochemical properties of the composites as anode materials for lithium-ion batteries were evaluated by galvanostatical method and cyclic voltammetry（CV）.We found that after acid treatment the sample possessed a reversible capacity of 446 mAh·g-1 after 50 cycles and excellent cycle stability.This indicates that OC is a suitable matrix to buffer against volume expansion and to prevent the agglomeration of SnO2 nanoparticles.