Related Experiment Video
Updated: Jun 21, 2026
06:34
In Situ Monitoring of Diffusion of Guest Molecules in Porous Media Using Electron Paramagnetic Resonance Imaging
Published on: September 2, 2016
Acceleration of diffusion in ethylammonium nitrate ionic liquid confined between parallel glass plates
Andrei Filippov1, Oleg I Gnezdilov2, Nicklas Hjalmarsson3
1Chemistry of Interfaces, Luleå University of Technology, SE-97187 Luleå, Sweden. Andrei.Filippov@ltu.se and Institute of Physics, Kazan Federal University, 420008 Kazan, Russia.
Physical Chemistry Chemical Physics : PCCP
|September 22, 2017
Summary
The diffusion of ethyl-alkane-nitrile (EAN) between polar glass plates is about twice as fast as in bulk. This suggests the formation of a distinct EAN phase under confinement.
Area of Science:
- Physical Chemistry
- Materials Science
Background:
- Confinement effects significantly alter the physical properties of liquids.
- Understanding molecular behavior in confined geometries is crucial for designing advanced materials and devices.
Purpose of the Study:
- To investigate the diffusion dynamics of ethyl-alkane-nitrile (EAN) under confinement.
- To compare confined EAN diffusion with bulk EAN diffusion.
Main Methods:
- Utilizing diffusion measurements within a controlled micro-gap between polar glass plates.
- Comparing experimental diffusion coefficients with established bulk values.
Main Results:
- Observed a diffusion enhancement of approximately a factor of two for confined EAN compared to bulk EAN.
- The enhanced diffusion suggests altered molecular interactions and/or phase behavior.
Conclusions:
- Confinement between polar glass plates induces a distinct phase of EAN with significantly higher diffusion rates.
- The findings highlight the importance of interfacial interactions and confinement on molecular transport properties.
Related Concept Videos
01:12Diffusion
Diffusion is the passive movement of substances down their concentration gradients—requiring no expenditure of cellular energy. Substances, such as molecules or ions, diffuse from an area of high concentration to an area of low concentration in the cytosol or across membranes. Eventually, the concentration will even out, with the substance moving randomly but causing no net change in concentration. Such a state is called dynamic equilibrium, which is essential for maintaining overall...
03:48Behavior of Gas Molecules: Molecular Diffusion, Mean Free Path, and Effusion
Although gaseous molecules travel at tremendous speeds (hundreds of meters per second), they collide with other gaseous molecules and travel in many different directions before reaching the desired target. At room temperature, a gaseous molecule will experience billions of collisions per second. The mean free path is the average distance a molecule travels between collisions. The mean free path increases with decreasing pressure; in general, the mean free path for a gaseous molecule will be...
01:24Protein Diffusion in the Membrane
Proteins show rotational as well as lateral diffusion across the membrane. The lateral diffusion of proteins was confirmed through the cell fusion experiment where mouse and human cells were fused, resulting in hybrid cells. When the human and mouse cells fused, the specific membrane proteins on human and mouse cells were marked with the red and green-fluorescent markers, respectively. Initially, the red and green fluorescence was located on the respective hemisphere of the cell. As time...
01:07Diffusion on Chromatography Columns
In column chromatography, when an analyte is introduced as a narrow band at the top of the column, the solutes begin to separate and broaden, developing a Gaussian profile. This broadening occurs due to various factors, such as longitudinal diffusion.
Longitudinal diffusion occurs when the solute molecules in the mobile phase diffuse from the more concentrated center of the chromatographic band to the more dilute regions on either side, both towards and against the flow direction. This...
Longitudinal diffusion occurs when the solute molecules in the mobile phase diffuse from the more concentrated center of the chromatographic band to the more dilute regions on either side, both towards and against the flow direction. This...
01:31Transport Number
The transport number is the fraction of the total current carried by an ion in an electrolyte solution. It is defined as the ratio of the current carried by a specific ion to the total current flowing through the solution. The transport number, t, is central to understanding ionic mobility, which describes how fast an ion moves under the influence of an electric field. This link connects the physical behavior of ions in solution to the chemical processes that occur during electrochemical...
01:17Steady, Laminar Flow Between Parallel Plates
Understanding steady, laminar flow between parallel plates is essential for analyzing and designing flow in narrow rectangular channels, commonly found in various water conveyance and drainage systems. The Navier-Stokes equations govern fluid motion and are generally challenging to solve due to their nonlinearity. However, simplifications are possible in certain cases, like the steady laminar flow between parallel plates. For this scenario, we assume steady, incompressible, laminar flow.