In a examine printed in Nature Chemical Engineering, researchers at EPFL developed a scalable methodology for producing porous graphene membranes that effectively separate carbon dioxide.
The event might considerably scale back the associated fee and footprint of carbon seize applied sciences.
Capturing CO₂ from industrial emissions is important in addressing local weather change. Nonetheless, present strategies, equivalent to chemical absorption, are each costly and energy-intensive. Graphene, a skinny, ultra-strong materials, has lengthy been thought-about a possible various for gasoline separation. Nonetheless, producing massive, environment friendly graphene membranes has been difficult.
Led by Professor Kumar Agrawal of the Gaznat Chair in Superior Separations, researchers at EPFL have developed a scalable strategy to create porous graphene membranes that selectively filter CO₂ from gasoline mixtures. This methodology reduces manufacturing prices whereas bettering membrane high quality and efficiency, which might facilitate real-world functions in carbon seize and different areas.
Graphene membranes will be engineered with particular pores that enable CO₂ to go by way of whereas blocking bigger molecules like nitrogen, making them best for gasoline separation. These properties make them appropriate for capturing CO₂ emissions from energy vegetation and industrial processes. Nonetheless, producing these membranes at scale has been each tough and dear.
Most current methods use costly copper foils to provide high-quality graphene, and the fragile dealing with typically leads to fractures that compromise membrane efficiency. The problem has been growing an economical, constant methodology for producing massive, high-quality graphene membranes.
The EPFL staff tackled these challenges by growing a way to develop high-quality graphene on low-cost copper foils, considerably lowering materials prices. In addition they refined a chemical course of utilizing ozone (O₃) to etch microscopic pores into the graphene, enabling extremely selective CO₂ filtration.
The researchers enhanced the interplay between the gasoline and graphene, leading to uniform pore improvement throughout massive areas. It is a essential step towards making the know-how commercially scalable.
To deal with the difficulty of membrane fragility, the staff additionally developed a singular switch methodology. As an alternative of floating the fragile graphene sheet onto a assist, which regularly results in cracks, they employed a direct switch approach throughout the membrane module. This strategy eliminates dealing with challenges and reduces failure charges to almost zero.
Utilizing this novel methodology, the researchers efficiently created 50 cm² graphene membranes with near-perfect integrity, surpassing earlier limitations. These membranes demonstrated sturdy gasoline permeance and CO₂ selectivity, successfully permitting CO₂ to go by way of whereas blocking different gases.
Optimizing the oxidation course of elevated the density of CO₂-selective pores, additional bettering the membrane’s efficiency. Computational fashions confirmed that rising the gasoline circulation over the membrane was key to attaining these outcomes.
This improvement has the potential to considerably affect carbon seize know-how. Conventional CO₂ seize strategies depend on energy-intensive chemical processes, making them tough and dear for widespread use. In distinction, graphene membranes require no warmth enter and function by way of easy pressure-driven filtration, providing substantial vitality financial savings.
Past carbon seize, this know-how might be utilized to separate different gases, equivalent to hydrogen and oxygen. With its scalable manufacturing approach and low-cost elements, this breakthrough brings graphene membranes nearer to business viability.
GAZNAT, the Swiss Federal Workplace of Vitality, Bridge (Proof of Idea), and the Canton of Valais funded the examine.
Journal Reference:
Hao, J. et al. (2025) Scalable synthesis of CO2-selective porous single-layer graphene membranes. Nature Chemical Engineering. doi.org/10.1038/s44286-025-00203-z
