Related Experiment Video
Updated: Jun 30, 2025
07:51
Development and Functionalization of Electrolyte-Gated Graphene Field-Effect Transistor for Biomarker Detection
Published on: February 1, 2022
3.2K
Selective ion transport in large-area graphene oxide membrane filters driven by the ionic radius and electrostatic
Lidia Lancellotti1, Antonio Bianchi1, Alessandro Kovtun1
1Institute for Organic Synthesis and Photoreactivity, National Research Council (ISOF-CNR), via Piero Gobetti 101, 40129, Bologna, BO, Italy. palermo@isof.cnr.it.
Nanoscale
|March 19, 2024
Summary
Graphene oxide filters demonstrate selective ion transport, blocking divalent ions while allowing monovalent ions through. This breakthrough utilizes carboxylate group interactions on the graphene oxide surface for efficient water purification.
Area of Science:
- Materials Science
- Nanotechnology
- Environmental Engineering
Background:
- Graphene oxide (GO) filters show potential for water purification and ion sieving.
- The precise mechanism of ion sieving in GO filters remains under investigation.
- Existing GO filters typically have small areas and simple planar geometries.
Purpose of the Study:
- To develop and characterize graphene oxide filters on hollow fiber membranes for enhanced ion sieving.
- To elucidate the mechanism behind selective ion transport in graphene oxide filters.
- To demonstrate the efficacy of these filters for separating monovalent and divalent ions.
Main Methods:
- Fabrication of uniform graphene oxide coatings on hollow fiber filters.
- Ion transport measurements under applied electric voltage.
- Adsorption studies, molecular dynamics simulations, and spectroscopic characterization.
Main Results:
- Achieved uniform GO coatings on complex hollow fiber geometries without defects.
- Demonstrated selective transport of monovalent ions (Na+, K+) while blocking divalent ions.
- Unraveled the sieving mechanism, identifying interactions with carboxylate groups at neutral pH as key.
Conclusions:
- Graphene oxide hollow fiber filters offer a scalable solution for selective ion separation.
- The ion sieving mechanism is primarily governed by surface chemistry, specifically carboxylate group interactions.
- These filters represent a significant advancement in water purification technologies.
More Related Videos
Related Concept Videos
01:15Potentiometry: Membrane Electrodes
574
Membrane electrodes, also known as p-ion electrodes, use membranes that selectively interact with free analyte ions, generating a potential difference across the membrane. The resulting membrane potential, known as the asymmetry potential, is not zero even when analyte concentrations on both sides of the membrane are equal. The membrane's response is typically not selective to a single analyte but proportional to the concentration of all ions in the sample solution capable of interacting at...
574
01:44The Significance of Membrane Transport
25.8K
The transport of solutes across the cell membrane is essential for metabolic processes, like maintaining cell size and volume, generating the action potential, exchanging nutrients and gases, etc. Membrane transport can be either passive or active. It can be simple diffusion, facilitated, or mediated transport aided by transport proteins such as transporters and channels.
Transporters facilitate either an active or passive movement of solutes. They can allow a single-molecule transport down its...
Transporters facilitate either an active or passive movement of solutes. They can allow a single-molecule transport down its...
25.8K
01:16Facilitated Diffusion
455
The plasma membrane, a critical structure in cellular biology, houses an array of transporters, or carrier proteins, interspersed within its lipid bilayer. These proteins play a crucial role in solute transport through facilitated diffusion, a form of passive diffusion that uses transporters to move the molecules across the membrane.
In this process, substrates such as organic compounds and ions interact with a transporter on one side, triggering conformational changes in proteins that enable...
In this process, substrates such as organic compounds and ions interact with a transporter on one side, triggering conformational changes in proteins that enable...
455
01:32Secondary Active Transport
7.0K
One example of how cells use the energy contained in electrochemical gradients is demonstrated by glucose transport into cells. The ion vital to this process is sodium (Na+), which is typically present in higher concentrations extracellularly than in the cytosol. Such a concentration difference is due, in part, to the action of an enzyme "pump" embedded in the cellular membrane that actively expels Na+ from a cell. Importantly, as this pump contributes to the high concentration of...
7.0K
01:15Dialysis
662
Dialysis is a diffusion-based purification process that separates analyte molecules from a complex matrix. This is accomplished by allowing molecules in the solution to pass through a semipermeable membrane into a liquid on the other side. The membrane is usually made of cellulose acetate or cellulose nitrate, and the second liquid must be miscible with the solution. Ions (e.g., chloride or sodium) or organic molecules (e.g., glucose) can pass through the membrane pores, which generally have...
662
01:29Primary Active Transport
10.2K
In contrast to passive transport, active transport involves a substance being moved through membranes in a direction against its concentration or electrochemical gradient. There are two types of active transport: primary active transport and secondary active transport. Primary active transport utilizes chemical energy from ATP to drive protein pumps embedded in the cell membrane. With energy from ATP, the pumps transport ions against their electrochemical gradients—a direction they would...
10.2K