Drastically Reduced Ion Mobility in a Nanopore Due to Enhanced Pairing and Collisions between Dehydrated Ions

Citations Over TimeTop 10% of 2019 papers

Abstract

Ion transport through nanopores is a process of fundamental significance in nature and in engineering practice. Over the past decade, it has been found that the ion conductivity in nanopores could be drastically enhanced, and different mechanisms have been proposed to explain this observation. To date, most reported studies have been carried out with relatively dilute electrolytes, while ion transport in nanopores under high electrolyte concentrations (>1 M) has been rarely explored. Through systematic experimental and atomistic simulation studies with NaCl solutions, here we show that at high electrolyte concentrations, ion mobility in small nanopores could be significantly reduced from the corresponding bulk value. Subsequent molecular dynamics studies indicate that in addition to the low mobility of surface-bound ions in the Stern layer, enhanced pairing and collisions between partially dehydrated ions of opposite charges also make important contributions to the reduced ion mobility. Furthermore, we show that the extent of mobility reduction depends on the association constant between cations and anions in different electrolytes with a more drastic reduction for a larger association constant.

Related Papers

• → Nuclear pairing models(1992)403 cited
• → Slowing single-stranded DNA translocation through a solid-state nanopore by decreasing the nanopore diameter(2014)77 cited
• → Pairing symmetry in layered BiS2 compounds driven by electron-electron correlation(2014)55 cited
• → Axial shape and pairing evolution of 82−106Zr, 86−112Mo, 90−116Ru and 94−122Pd isotopic chains in the framework of the deformed BCS approach(2021)1 cited
• → Quasiparticle interference testing the possible pairing symmetry in Sr₂RuO₄*(2020)