Qi Shaowei, Zhang Xinghao, Lv Wei, Zhang Yunbo, Kong Debin, Huang Zhijia, Yang Quan-Hong
CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience , National Center for Nanoscience and Technology , Beijing 100190 , P. R. China.
Nanoyang Group, State Key Laboratory of Chemical Engineering, School of Chemical Engineering and Technology , Tianjin University , Tianjin 300072 , China.
ACS Appl Mater Interfaces. 2019 Apr 17;11(15):14142-14149. doi: 10.1021/acsami.9b02206. Epub 2019 Apr 4.
Building a stable electrode structure is an effective way to promote the practical applications of Si anode, which has large volume changes during charge/discharge process, in lithium-ion batteries. Herein, we fabricated an integrated electrode structure reinforced from "internal" to "external" to boost the performance of Si nanoparticles (NPs). The electrode contains the conductive polymer of poly(3,4-ethylene dioxythiophene):poly(styrenesulphonic acid) (PEDOT:PSS) as the binder, reduced graphene oxide (rGO), and hydroxylated Si NPs, which help form the "internal" interaction between them through the hydrogen bonding, while the "external" malleable network built by the flexible polymers and two-dimensional rGO sheets as the framework endows the highly flexible network to accommodate the Si expansion and forms long-range conductive network. Thus, the built-integrated electrode by the simple casting method shows high capacity, good rate performance, and long cycling stability. It is noted that such an electrode shows a high areal capacity of 3.29 mA h cm and a high volumetric capacity of 3290 A h cm at 0.09 mA cm. The integrated electrode design is promising to promote the practical use of Si anodes and can be extended to other noncarbon anodes with large volume changes.
构建稳定的电极结构是促进硅阳极在锂离子电池中实际应用的有效途径，硅阳极在充放电过程中会发生较大的体积变化。在此，我们制备了一种从“内部”到“外部”增强的集成电极结构，以提高硅纳米颗粒（NPs）的性能。该电极包含聚（3,4-亚乙基二氧噻吩）：聚（苯乙烯磺酸）（PEDOT:PSS）导电聚合物作为粘结剂、还原氧化石墨烯（rGO）和羟基化硅纳米颗粒，它们通过氢键有助于在它们之间形成“内部”相互作用，而由柔性聚合物和二维rGO片材构建的“外部”可延展网络作为框架赋予高度柔性的网络以适应硅的膨胀并形成长程导电网络。因此，通过简单浇铸法制备的集成电极表现出高容量、良好的倍率性能和长循环稳定性。值得注意的是，这种电极在0.09 mA cm下显示出3.29 mA h cm的高面积容量和3290 A h cm的高体积容量。集成电极设计有望促进硅阳极的实际应用，并可扩展到其他具有大体积变化的非碳阳极。
