• 文献标题:   Effect of Structural Disorders on the Li Storage Capacity of Graphene Nanomaterials: A First-Principles Study
  • 文献类型:   Article
  • 作  者:   TSAI YJ, KUO CL
  • 作者关键词:   liion battery, structural disorder in graphene, amorphous graphene, density functional theory
  • 出版物名称:   ACS APPLIED MATERIALS INTERFACES
  • ISSN:   1944-8244 EI 1944-8252
  • 通讯作者地址:   Natl Taiwan Univ
  • 被引频次:   0
  • DOI:   10.1021/acsami.0c04188
  • 出版年:   2020

▎ 摘  要

We employed first-principles calculations to investigate the effect of structural disorders on the Li storage capacity of graphene nanomaterials. Our calculations first revealed that the Li storage capacity of a graphene monolayer does not necessarily increase with the size of a C vacancy created but is largely determined by the local geometry of the defect sites. Our electronic structure analysis further revealed that the enhanced Li storage capacity by the C vacancy defect is mainly attributed to the increased number of the unoccupied electronic density of states lying near the Fermi level, which can be substantially increased by raising the number of bond rotations within the vacancy sites. Furthermore, it was also found that the Li storage capacity of graphene can be effectively enhanced by increasing the degree of local ring disorders without the presence of any vacancy defect. The amorphous graphene structure was shown to possess a relatively higher Li storage capacity compared to pristine graphene, primarily owing to the presence of many nonhexagonal rings randomly distributed in the graphene lattice. These nonhexagonal rings can create many electron-deficient regions on the graphene surface to effectively accommodate more electrons from Li, thereby substantially enhancing the Li storage capacity of graphene nanomaterials.