• 文献标题:   Multi-layer graphene oxide alone and in a composite with nanosilica: Preparation and interactions with polar and nonpolar adsorbates
  • 文献类型:   Article
  • 作  者:   GUN KO VM, TUROV VV, ZARKO VI, GONCHARUK OV, MATKOVSKY AK, PRYKHOD KO GP, NYCHIPORUK YM, PAKHLOV EM, KRUPSKA TV, BALAKIN DY, CHARMAS B, ANDRIYKO LS, SKUBISZEWSKAZIEBA J, MARYNIN AI, UKRAINETS AI, KARTEL MT
  • 作者关键词:   mlgo, nanosilica, polar adsorbate, nonpolar adsorbate, interfacial phenomena, freezingmelting hysteresis effect
  • 出版物名称:   APPLIED SURFACE SCIENCE
  • ISSN:   0169-4332 EI 1873-5584
  • 通讯作者地址:   Chuiko Inst Surface Chem
  • 被引频次:   1
  • DOI:   10.1016/j.apsusc.2016.06.196
  • 出版年:   2016

▎ 摘  要

Freeze-dried multi-layer graphene oxide (MLGO), produced from natural flake graphite using ionic hydration method, demonstrates strong interactions of functionalized carbon sheets with polar or nonpolar adsorbates or co-adsorbates depending on the characteristics of dispersion media. Interactions of MLGO with a mixture of water and n-decane in chloroform media provide specific surface area (Se) in contact with unfrozen liquids greater than 1000 m(2)/g corresponding to stacks with 3-5 carbon layers. Electrostatic interactions between functionalized carbon sheets in dried MLGO are very strong. Therefore, nonpolar molecules (benzene, decane, nitrogen) cannot penetrate between the sheets. Water molecules can effectively penetrate between the sheets, especially if MLGO is located in weakly polar CDCL3 medium. In this case, n-decane molecules (co-adsorbate) can also penetrate into the sheet stacks and locate around nonpolar fragments of the sheets. The S-u value of MLGO being in contact with unfrozen water can reach 360 m(2)/g, but upon co-adsorption of water with decane S-u = 930 m(2)/g, i.e., hydrophobic interactions of the mentioned fragments with decane are stronger that with co-adsorbed water. Water alone (0.25 or 0.5 g/g) bound to MLGO in a mixture with fumed silica A-300 in air or CDCL3 media can provide S-u =30-50 m(2)/g. Pores in wetted MLGO or MLGO/A-300 mainly correspond to mesopores. Nanosilica does not provide significant opening of the MLGO sheet stacks during their mechanical mixing. (C) 2016 Elsevier B.V. All rights reserved.