• 文献标题:   Graphene Transistor as a Probe for Streaming Potential
  • 文献类型:   Article
  • 作  者:   NEWAZ AKM, MARKOV DA, PRASAI D, BOLOTIN KI
  • 作者关键词:   graphene, streaming potential, electric double layer, flow sensor, ionic strength sensor, microfluidic
  • 出版物名称:   NANO LETTERS
  • ISSN:   1530-6984
  • 通讯作者地址:   Vanderbilt Univ
  • 被引频次:   30
  • DOI:   10.1021/nl300603v
  • 出版年:   2012

▎ 摘  要

We explore the dependence of electrical transport in a graphene field effect transistor (GraFET) on the flow of water/sodium chloride electrolyte within the immediate vicinity of that transistor. We find large and reproducible shifts in the charge neutrality point of GraFETs that are dependent on the liquid velocity and the ion concentration. We show that these shifts are consistent with the variation of the local electrochemical potential of the liquid next to graphene that are caused by the fluid flow (streaming potential). Furthermore, we utilize the sensitivity of electrical transport in GraFETs to the parameters of the fluid flow to demonstrate graphene-based mass flow and ionic concentration sensing. We successfully detect a flow as small as similar to 70 nL/min and detect a change in the ionic concentration as small as similar to 40 nM.