• 文献标题:   The Influence of the Size and Oxidation Degree of Graphene Flakes on the Process of Creating 3D Structures during Its Cross-Linking
  • 文献类型:   Article
  • 作  者:   KACZMAREK L, WARGA T, MAKOWICZ M, KYZIOL K, BUCHOLC B, MAJCHRZYCKI L
  • 作者关键词:   graphene, graphene oxide, crosslinking, 3d structure
  • 出版物名称:   MATERIALS
  • ISSN:  
  • 通讯作者地址:   Lodz Univ Technol
  • 被引频次:   1
  • DOI:   10.3390/ma13030681
  • 出版年:   2020

▎ 摘  要

This article presents the results of the cross-linking of oxidized flake graphene (GO) using hydrazine at room temperature. Conducting the process at temperatures up to 30 degrees C allowed to eliminate the phenomenon of thermal GO reduction to its non-oxidized form. In addition, based on the Infrared and Raman spectroscopy as well as X-ray photoelectron spectroscopy (XPS) analysis, the cross-linking ability of GO was observed depending on its size and degree of oxidation. These parameters were associated with selected physicochemical and electrical properties of obtained 3D structures. Three GO flakes sizes were tested in three different oxidation degrees. It was shown that, regardless of the size of GO, it is crucial to achieve a specific oxidation degree threshold which for the conducted tests was a >20% share of oxygen atoms in the whole structure. This value determines the ability to cross-link with hydrazine thanks to which it is possible to synthesize the spatial structure in which the pi-pi interactions among individual flakes are significantly reduced. This directly translates into the fact that the 3D structure shows an electrical resistance value in the range of 4-103 Omega, depending on the size and oxidation degree of the used material. The explanation of this phenomenon related to the electrical conductivity of 3D structures was confirmed based on the molecular modeling of the chemical structures.