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Scalable Syntheses of Graphene Oxide and Reduced Graphene Oxide using Cascade Design Oxidation and Highly Basic Reduction Reactions
Published on: July 3, 2025
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Selective Gas Permeation in Graphene Oxide-Polymer Self-Assembled Multilayers.
Davide Pierleoni, Matteo Minelli, Simone Ligi1
1Graphene-XT srl , via D'Azeglio 15 , I-40123 Bologna , Italy.
ACS Applied Materials & Interfaces
|March 10, 2018
Summary
New graphene oxide (GO) and poly(ethyleneimine) (PEI) multilayer membranes overcome the Robeson limit for gas separation. These membranes achieve record gas permeability and selectivity, enabling efficient large-scale applications.
Area of Science:
- Materials Science
- Chemical Engineering
- Nanotechnology
Background:
- Polymer-based membranes for gas separation face limitations due to the Robeson limit, which balances permeability and selectivity.
- Achieving simultaneous high gas permeability and selectivity remains a significant challenge in membrane technology.
Purpose of the Study:
- To develop advanced membranes that surpass the Robeson limit for gas separation.
- To investigate the potential of graphene oxide (GO) and poly(ethyleneimine) (PEI) multilayers for enhanced membrane performance.
Main Methods:
- Fabrication of multilayered membranes using graphene oxide (GO) and poly(ethyleneimine) (PEI).
- Characterization of the membrane structure, including spacing and periodicity.
- Evaluation of gas separation performance, including permeability and selectivity for various gases.
Main Results:
- A highly reproducible, periodic multilayered structure with 3.7 nm spacing was achieved.
- The membranes demonstrated a record combination of high gas permeability and selectivity, exceeding the Robeson limit.
- Exceptional selectivity up to 500 for He/CO2 was observed.
- Gas permeability showed an exponential dependence on molecular diameter, indicating a precise sieving mechanism.
Conclusions:
- GO/PEI multilayer membranes offer a novel approach to overcome the traditional trade-offs in gas separation.
- The tunable permeability and high selectivity make these membranes suitable for large-scale industrial applications.
- This technology represents a significant advancement in membrane-based gas separation.
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