Fabrication of Highly-Aligned, Conductive, and Strong Graphene Papers Using Ultralarge Graphene Oxide Sheets
详细信息 查看全文
- 作者：Xiuyi Lin ; Xi Shen ; Qingbin Zheng ; Nariman Yousefi ; Lin Ye ; Yiu-Wing Mai ; Jang-Kyo Kim
- 刊名：ACS Nano
- 出版年：2012
- 出版时间：December 21, 2012
- 年：2012
- 卷：6
- 期：12
- 页码：10708-10719
- 全文大小：816K
- 年卷期：v.6,no.12(December 21, 2012)
- ISSN：1936-086X
文摘
This study demonstrates that large-size graphene oxide (GO) sheets can impart a tremendous positive impact on self-alignment, electrical conductivity, and mechanical properties of graphene papers. There is a remarkable, more than 3-fold improvement in electrical conductivity of the papers made from ultralarge GO sheets (with an average area of 272.2 渭m2) compared to that of the small GO counterpart (with an average area of 1.1 渭m2). The corresponding improvements in Young鈥檚 modulus and tensile strength are equally notable, namely 320% and 280%, respectively. These improvements of bulk properties due to the large GO sheets are correlated to multiscale elemental and structural characteristics of GO sheets, such as the content of carboxyl groups on the GO edge, C/O ratio and Raman D/G-band intensity ratio of GO on the molecular-scale, and the degree of dispersion and stacking behavior of GO sheets on the microscale. The graphene papers made from larger GO sheets exhibit a closer-stacked structure and better alignment as confirmed by the fast Fourier transform analysis, to the benefits of their electrical conductivity and mechanical properties. The molecular dynamics simulation further elucidates that the enhanced intersheet interactions between large GO sheets play a key role in improving the Young鈥檚 modulus of GO papers. The implication is that the said properties can be further improved by enhancing the intersheet stress transfer and electrical conduction especially through the thickness direction.