摘要:碳材料凭借其电极电位低,循环效率高,循环寿命长和安全性能好等优点成为锂离子电池的首选负极材料。目前商业生产中普遍使用传统石墨电极,其理论容量仅为372mAh/g,远远达不到我们对高性能锂离子电池的要求。本文旨在探索简易、大量制备新型纳米级碳材料用作高性能锂离子电池电极材料,开展的主要工作如下:在不同温度下(550℃、700℃和1100℃)运用高温催化裂解法制得碳包铁纳米颗粒,再通过酸洗和真空热处理依次除去铁核以及掺杂模板,得到多孔壁碳纳米笼并用于制成锂离子电池负极材料。研究不同制备温度下碳纳米笼的结构与形貌特性对锂离子电池性能上的影响。结果表明制备温度越高,石墨化程度越好,碳纳米笼结构越稳定,电池寿命也越长,但是,比表面积也相应减少,电池储锂能力减弱。因此,在700℃制备的多孔壁碳纳米笼兼具有良好石墨化程度和高比表面积的优点,相比于其他碳负极材料,具有可逆容量高,循环容量高,稳定性好等优势,具有很好的商业化前景。41770
毕业论文关键字:碳纳米笼;高比表面积;负极材料;锂离子电池
Synthesis of porous-walled carbon nanocages towards high performance anodes of lithium-ion batteries
Abstract: Amongst the candidates for the anode materials of lithium-ion batteries, carbonaceous materials are dominant because of their outstanding properties. Graphite, the mainstay of the commercial anode materials, delivers a limited specific capacity of 372mAh/g, which can hardly meet the requirement of high-performance lithium-ion batteries. In this work, facile and large production of graphitic nanomaterials has been carried out towards high performance lithium-ion batteries. Majority of our work has been listed as followed: utilizing catalytic pyrolysis to produce GNCs at different temperature(550, 700 and 1100 ºC), and then removing the core of the particle by acid-treatment and removing doping structure by air-oxidization at 300 ºC to get graphitic nanocages (GNCs) with porous shells, which are used as the anodes for lithium-ion battery. According to the performance of GNCs prepared at different temperature, their graphitization and stability were enhanced, with synthetic temperature rising, which traded off specific surface area and capacity as well. Thus, the porous shell GNCs produced at 700 ºC with both high graphitization and specific surface area leads to its high reversible capacity and good stability. Such prepared GNCs would be a promising anode material towards Li ion battery applications.
Key Words:Carbon nanocages; High specific surface area; anode materials; Lithium-ion batteries
目 录
1 绪论 1
1.1 碳材料简介 1
1.2 碳的同素异形体 2
1.2.1 碳的价键结构 2
1.2.2 富勒烯 2
1.2.2 碳纳米管 3
1.2.3 空心碳纳米笼 4
1.2.4 石墨烯 4
1.3 碳纳米材料的制备方法 5
1.3.1 模板法 6
1.3.2 化学气相沉积法 7
1.3.3 催化裂解法 7
1.4 碳纳米材料的应用 7
1.4.1 在超级电容器中的应用 7
1.4.2 在锂离子电池中的应用 8
1.4.3 碳纳米材料作为催化剂载体 8
1.5 锂离子电池简介 9
1.6 本文的主要研究内容和意义 11
2 实验部分 12
2.1 材料制备 12
2.1.1 原料试剂 12
2.1.2 实验设备 12
2.1.3 碳纳米笼的制备 12
2.2 材料性能表征 13 多孔壁碳纳米笼用于锂电负极材料的研究:http://www.youerw.com/cailiao/lunwen_41952.html