Laboratory for Surface Science and Technology, Department of Materials, ETH Zürich, Switzerland; Laboratory for Advanced Fibers, Empa Materials Science & Technology, St. Gallen, Switzerland.
Laboratory for Surface Science and Technology, Department of Materials, ETH Zürich, Switzerland; Laboratory for Smart Interfaces in Environmental Nanotechnology, Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, IL, USA.
J Colloid Interface Sci. 2017 Nov 15;506:263-270. doi: 10.1016/j.jcis.2017.07.039. Epub 2017 Jul 14.
We probe counter-ion specific effects in nano-confined electrical-double-layers (EDLs) by means of direct force measurements across a model slit pore in the extended surface forces apparatus. By variation of solution composition, we compare four different counter-ions with dissimilar hydration properties, namely Na, K, Cs as well as HO, all confined between (001) mica surfaces. We discuss the results in terms of a recently proposed π-transition model, evoking hydrated ion layering as the recurrent structural element in highly confined EDLs. We demonstrate that the π-transition essentially proceeds in multiple steps in coherence with the event of single- or multiple- hydrated-ion layering.
我们通过扩展表面力仪中的模型狭缝孔进行直接力测量，探究纳米受限双电层（EDL）中的抗衡离子特异性效应。通过改变溶液组成，我们比较了四种具有不同水合性质的不同抗衡离子，即 Na、K、Cs 以及 HO，它们都被限制在（001）云母表面之间。我们根据最近提出的π 跃迁模型讨论了这些结果，该模型提出，在高度受限的 EDL 中，水合离子分层是反复出现的结构单元。我们证明，π 跃迁实质上是与单或多层水合离子分层的事件一致，分多个步骤进行。
