碳包覆纳米SnSb合金作为高性能钠离子电池负极材料  

Spherical Nano-SnSb/C Composite as a High-Performance Anode Material for Sodium Ion Batteries

作　　者：李海霞[1] 王纪伟[1] 焦丽芳[1] 陶占良[1] 梁静[1] Haixia Li;Jiwei Wang;Lifang Jiao;Zhanliang Tao;Jing Liang(Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education),College of Chemistry,Nankai University,Tianjin 300071,P.R.China)

机构地区：[1]南开大学化学学院,先进能源材料化学教育部重点实验室,天津300071

出　　处：《物理化学学报》2020年第5期99-106,共8页Acta Physico-Chimica Sinica

基　　金：国家重点研发计划(2016YFB0901500,2016YFB0101201);国家自然科学基金(51771094)资助项目。

摘　　要：采用喷雾热解法合成了碳包覆的SnSb/C合金复合材料,利用X射线粉末衍射仪(XRD)、场发射扫描电子显微镜(FESEM)、透射电子显微镜(TEM)等方法对产物的物相和形貌进行了表征,其中SnSb/C颗粒为10 nm左右的复合材料(10-SnSb/C)作为钠离子电池负极时,表现出优异的循环和倍率性能。首圈放电达到722.1 mAh·g^−1,首圈库仑效率86.3%,在100、1000、3000 mA·g^−1下比容量分别为607.7、645.4、452.2 mAh·g^−1,在1000 mA·g^−1电流下循环200周后可逆容量达到623 mAh·g^−1,容量保持率为95%。SnSb/C复合材料出色的储钠性能源于其完全被碳包裹的纳米结构,该结构可以有效提高活性物质的利用率,促进电子、离子的传导,并且抑制纳米粒子在长循环过程中的粉化和团聚。Sodium-ion batteries(SIBs) have recently garnered considerable attention because of the greater abundance, wider distribution, and lower cost of Na compared to Li. However, the investigation is insufficient, mainly because Na+ is larger and heavier than Li+, thereby limiting the Na+ insertion and extraction ability from the host materials. Anodes with alloying reactions such as Sn, Ge, and Sb have been considered for SIBs owing to their high gravimetric and volumetric specific capacities. In this study, we devised a onepot reaction strategy for the in-situ fabrication of a spherical porous nanoSnSb/C composite by employing aerosol spray pyrolysis, and subsequently applied it as an anode in SIBs. The products of spray pyrolysis generally feature three-dimensional spherical hierarchical structures, which are considered to be relatively stable and also act as high-packing-density electrode materials. Additionally, they can be easily handled during the fabrication of the electrode.By adjusting the precursor concentration of SnCl2·2H2O and SbCl3, different sizes for Sn Sb nanoparticles(10 and 20 nm) were obtained. The crystal structures and morphologies of the as-prepared samples were characterized using X-ray diffraction, field-emission scanning electron microscopy, and high-resolution transmission electron microscopy. Thermal gravimetric analysis was carried out to analyze the carbon content of SnSb/C composites by using a TG-DSC analyzer with a heating rate of 5 °C·min-1 in air from 25 °C to 600 °C. The specific surface areas of the microspheres were determined by Brunauer-Emmett-Teller analysis. X-ray photoelectron spectroscopy and Raman spectroscopy were used to investigate the studied materials. The micro-nanostructured composite is composed of Sn Sb nanoparticles(10 and 20 nm);moreover, the carbon content and size of Sn Sb nanograins could be controlled by altering the reaction conditions. Owing to its unique structure, the obtained nano-composite displays stable cycle performance and high rate capability

关 键 词：SnSb合金 钠离子电池 负极材料 喷雾热解 

分 类 号：O646[理学—物理化学] O641[理学—化学]