通过密的石墨烯基膜无阻地透水
R R Nair1, H A Wu, P N Jayaram
1School of Physics and Astronomy, University of Manchester, Manchester, UK.
Science (New York, N.Y.)
|January 28, 2012
概括
石墨烯氧化物膜阻断所有液体和气体,但允许快速的水透. 这是由于纳米通道中独特的低摩擦水流,使先进的分离技术成为可能.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 物理化学 物理化学
背景情况:
- 纳米孔透对于先进的过和分离材料至关重要.
- 在透过程中,在分子尺度上发生不寻常的现象.
- 石墨烯氧化物为膜设计提供了独特的特性.
研究的目的:
- 为了研究亚微米厚的氧化石墨烯膜的透性质.
- 了解水对其他分子的选择性运输.
- 探索这些膜在分离技术中的潜力.
主要方法:
- 制造亚微米厚的氧化石墨烯膜.
- 测试膜对各种液体,蒸汽和气体 (包括) 的不透性.
- 测量水 (H2O) 的透率,并将其与 (He) 进行比较.
主要成果:
- 石墨烯氧化物膜证明了对液体,蒸汽和等气体的完全无性.
- 水以显著更高的速度 (至少比快10^10倍) 穿透膜.
- 在由石墨烯板形成的二维毛细血管内,水单层的低摩擦流被确定为机制.
结论:
- 石墨烯氧化物膜具有选择性透性,阻断大多数分子,同时允许不受阻碍的水流.
- 观察到的现象归因于水与氧化石墨烯纳米通道相互作用的独特结构和特性.
- 这些发现为使用基于氧化石墨烯的材料的新型过和分离应用铺平了道路.
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