Fluorinated multi-walled carbon nanotubes as cathode materials of lithium and sodium primary batteries: effect of graphitization of carbon nanotubes
Fluorinated multi-walled carbon nanotubes as cathode materials of lithium and sodium primary batteries: effect of graphitization of carbon nanotubes
复制标题
氟化多壁碳纳米管作为锂钠原电池正极材料：碳纳米管石墨化的影响
DOI：
10.1039/c8ta12074a
复制
发表时间：
2019-03-28
影响因子：
11.9
通讯作者：
Zhou, Jin
中科院分区：
文献类型：
--
作者：
Li, Yanyan;Wu, Xiaozhong;Zhou, Jin
锂/氟化碳（Li/CFx）电池是一种广泛使用的固态锂原电池（LPB），具有迄今为止已知的最高比能量。然而，锂资源的稀缺迫使研究人员探索其他类型的电池。由于钠的低成本及其与锂相似的化学性质，钠电池被认为是最合适的候选电源。本工作制备了两个系列的氟化碳纳米管，即氟化普通碳纳米管（FCNT-x）和氟化石墨化碳纳米管（FGCNT-x）。系统研究了碳纳米管石墨化对氟化碳纳米管结构和碳-氟键合的影响。在相同的煅烧温度下，石墨化碳纳米管制备的FGCNT-x的F/C比和C-F键强度均低于普通碳纳米管制备的FCNT-x。FGCNT-0.81在锂和钠原电池中表现出非常高的比容量，分别为798.8和751 mA h g（-1），几乎达到使用F/C比计算的理论容量。此外，FGCNT-0.81在Li/CFx电池中具有2006.6W·h·kg（-1）的最大能量密度，在Na/CFx电池中具有1733.4W·h·kg（-1）的最大能量密度。Li/CFx和Na/CFx电池的最大功率密度分别可达3861.1（FCNT-0.81）和1863.9 W h kg（-1）（FGCNT-0.81）。结果表明，碳氟键的结合能、金属离子的电负性和极化力共同决定了碳纳米管的电化学性能。新型Na/CFx一次电池在低功率、高能量密度、低成本等领域具有广阔的应用前景。
The lithium/fluorinated carbon (Li/CFx) battery is a widely used solid-state lithium primary battery (LPB) with the highest ever known specific energy. However, the scarcity of lithium resources compels researchers to explore other types of batteries. Sodium batteries have been considered as the most suitable candidate power sources due to the low cost of sodium and its similar chemistry to lithium. In this work, we prepared two series of fluorinated carbon nanotubes (CNTs), which are fluorinated common CNTs (FCNT-x) and fluorinated graphitized CNTs (FGCNT-x). The effects of graphitization of the CNTs on the structure of fluorinated carbon nanotubes and C-F bonding are systematically studied. FGCNT-x prepared from the graphitized CNTs exhibit a lower ratio of F/C and weaker C-F bonding than those of the FCNT-x prepared from ordinary CNTs at the same fluorination temperature. FGCNT-0.81 exhibits very high specific capacities of 798.8 and 751 mA h g(-1) in lithium and sodium primary batteries, nearly reaching the theoretical capacity calculated using the F/C ratio. Besides, FGCNT-0.81 possesses a maximum energy density of 2006.6 W h kg(-1) in Li/CFx batteries and 1733.4 W h kg(-1) in Na/CFx batteries. The maximum power density for Li/CFx and Na/CFx batteries could reach up to 3861.1 (FCNT-0.81) and 1863.9 W h kg(-1) (FGCNT-0.81), respectively. It is proved that the binding energy of the C-F bond, the electronegativity and the polarization force of the metal ions collaboratively determine the electrochemical performance of the fluorinated CNTs. The new-type Na/CFx primary batteries developed here are promising in low power applications such as high-energy density and low-cost batteries.