scholarly journals Non-scaling behavior of electroosmotic flow in voltage-gated nanopores

2017 ◽  
Vol 19 (1) ◽  
pp. 450-457 ◽  
Author(s):  
Cheng Lian ◽  
Alejandro Gallegos ◽  
Honglai Liu ◽  
Jianzhong Wu
Keyword(s):  
Electrical Conductivity ◽  
Ion Transport ◽  
Pore Size ◽  
Size Effects ◽  
Electroosmotic Flow ◽  
Scaling Behavior ◽  
Double Layers ◽  
Electric Double Layers ◽  
Voltage Gated ◽  
Ionic Size

Ionic size effects and electrostatic correlations result in the non-monotonic dependence of the electrical conductivity on the pore size. For ion transport at a high gating voltage, the conductivity oscillates with the pore size due to a significant overlap of the electric double layers.

Effect of Membrane Pore Size and Membrane-Solute Interactions on Lysozyme Ultrafiltration

2006 ◽  
Vol 514-516 ◽  
pp. 1483-1487
Author(s):  
Vitor Magueijo ◽  
Viriato Semião ◽  
Maria Norberta de Pinho
Keyword(s):  
Molecular Weight ◽  
Pore Size ◽  
Pore Radius ◽  
Double Layers ◽  
Hydraulic Permeability ◽  
Average Pore ◽  
Average Pore Radius ◽  
Electric Double Layers ◽  
Membrane Pore ◽  
Cellulose Acetate Membranes

A model based on steric hindrance mechanisms [1] is used to determine the pore sizes of two ultrafiltration (UF) membranes. The lysozyme rejection coefficients of those membranes are predicted through the same model after modification of the pore size and solute radius by taking into account the development of electric double layers. Two asymmetric cellulose acetate membranes M1 and M2 were prepared and characterized. Membrane M1 has an hydraulic permeability of 2.1x10-6 m/s/bar, a molecular weight cut-off (MWCO) of 30,000 Da and an average pore radius of 2.6 nm. Membrane M2 has an hydraulic permeability of 5.9x10-6 m/s/bar, a molecular weight cut-off (MWCO) of 60,000 Da and an average pore radius of 5.3 nm. Aqueous solutions of lysozyme containing a NaCl concentration of 0.1M were ultrafiltrated through membranes M1 and M2. The predicted lysozyme rejections considering the development of electric double layers on the protein and membrane pore surfaces, are in good agreement with the experimental results.

Ionic size effects on the force between planar electrical double layers

1993 ◽  
Vol 97 (46) ◽  
pp. 12083-12086 ◽  
Author(s):  
Scott E. Feller ◽  
Donald A. McQuarrie
Keyword(s):  
Size Effects ◽  
Double Layers ◽  
Electrical Double Layers ◽  
Ionic Size

scholarly journals A gateway for ion transport on gas bubbles pinned onto solids

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Veton Haziri ◽  
Tu Pham Tran Nha ◽  
Avni Berisha ◽  
Jean-François Boily
Keyword(s):  
Ion Transport ◽  
Metal Ion ◽  
Electrochemical Impedance ◽  
Gas Bubbles ◽  
Open Circuit ◽  
Double Layers ◽  
Water Geochemistry ◽  
Chemical Potentials ◽  
Pore Water Geochemistry ◽  
Electric Potentials

AbstractGas bubbles grown on solids are more than simple vehicles for gas transport. They are charged particles with surfaces populated with exchangeable ions. We here unveil a gateway for alkali metal ion transport between oxygen bubbles and semi-conducting (iron oxide) and conducting (gold) surfaces. This gateway was identified by electrochemical impedance spectroscopy using an ultramicroelectrode in direct contact with bubbles pinned onto these solid surfaces. We show that this gateway is naturally present at open circuit potentials, and that negative electric potentials applied through the solid enhance ion transport. In contrast, positive potentials or contact with an insulator (polytetrafluoroethylene) attenuates transport. We propose that this gateway is generated by overlapping electric double layers of bubbles and surfaces of contrasting (electro)chemical potentials. Knowledge of this ion transfer phenomenon is essential for understanding electric shielding and reaction overpotential caused by bubbles on catalysts. This has especially important ramifications for predicting processes including mineral flotation, microfluidics, pore water geochemistry, and fuel cell technology.

Sign in / Sign up

Export Citation Format

Share Document