• 文献标题:   Nanoporosity Change on Elastic Relaxation of Partially Folded Graphene Monoliths
  • 文献类型:   Article
  • 作  者:   CHOTIMAH N, PUTRI AD, ONO Y, KENTO S, HATTORI Y, WANG SW, FUTAMURA R, URITA K, VALLEJOSBURGOS F, MORIGUCHI I, MORIMOTO M, CIMINO RT, NEIMARK AV, SAKAI T, KANEKO K
  • 作者关键词:  
  • 出版物名称:   LANGMUIR
  • ISSN:   0743-7463
  • 通讯作者地址:   Shinshu Univ
  • 被引频次:   6
  • DOI:   10.1021/acs.langmuir.7b03328
  • 出版年:   2017

▎ 摘  要

Fabrication of nanographene shows a promising route for production of designed porous carbons, which is indispensable for highly efficient molecular separation and energy storage applications. This process requires a better understanding of the mechanical properties of nanographene in their aggregated structure. We studied the structural and mechanical properties of nanographene monoliths compressed at 43 MPa over different times from 3 to 25 h. While in monoliths compressed over shorter time adsorption isotherms of Ar at 87 K or N-2 at 77 K exhibited a prominent hysteresis due to presence of predominant mesopores, compression for long time induces a low pressure hysteresis. On the other hand, compression for 25 h increases the microporosity evaluated by Ar adsorption, not by N-2 adsorption, indicating that 25 h compression rearranges the nanographene stacking structure to produce ultramicropores that can be accessible only for Ar. TEM, X-ray diffraction, and Raman spectroscopic studies indicated that the compression for 25 h unfolds double-bent-like structures, relaxing the unstable nanographene stacked structure formed on the initial compression without nanographene sheets collapse. This behavior stems from the highly elastic nature of the nanographenes.