• 文献标题:   Nanoscale ionic materials based on hydroxyl-functionalized graphene
  • 文献类型:   Article
  • 作  者:   WU LS, ZHANG BQ, LU H, LIU CY
  • 作者关键词:  
  • 出版物名称:   JOURNAL OF MATERIALS CHEMISTRY A
  • ISSN:   2050-7488 EI 2050-7496
  • 通讯作者地址:   Chinese Acad Sci
  • 被引频次:   24
  • DOI:   10.1039/c3ta14424k
  • 出版年:   2014

▎ 摘  要

Nanoscale ionic materials (NIMs) are novel organic-inorganic hybrid materials consisting of inorganic nanocore covalently attached with charged corona that is electrostatically coupled to oppositely charged canopy. In this study, graphene-based NIMs were prepared from hydroxyl-functionalized graphene (G-OH) that acquired via nitrene chemistry. The obtained G-OH-based NIM exhibited fluidity at its equivalence point (pH 6.3) at room temperature; in contrast, the graphene oxide (GO)-based NIM appeared as a black solid at its equivalence point because of the relatively low -OH density on GO. X-ray photoelectron spectroscopy and thermogravimetric analyses revealed grafting densities for G-OH and GO-based NIMs of ca. one polymer chain per 21 and 94 graphene carbon atoms, respectively. Microstructure analyses indicated the even dispersion of graphene nanosheets in NIMs. Rheological properties of G-OH-based NIMs could be adjusted over a wide range through variation of the volume fractions of canopy (Jeffamine M-2070 polyetheramine). G-OH-based NIMs also showed different viscoelastic behaviours from that of a G-OH-canopy physical mixture with similar graphene content. Thermal analyses showed that the crystallization temperature of canopy in G-OH-based NIMs decreased compared to that in physical mixtures. Cold crystallization was apparent during the heating cycle for G-OH-based NIMs, which did not exist for the physical mixtures. Furthermore, G-OH-based NIMs showed even dispersion and months-long stability in water and many organic solvents, indicating its amphiphilic nature. The unique properties of graphene-NIMs hold great potential for applications employing graphene-based materials.