Performance of GO laminated membranes in H2/CO2 separation as a function of the membrane thickness

• Published in: International journal of hydrogen energy 2024-11, Vol.90, p.646-654
• Main Authors: Carrio, Juan A.G., Echeverrigaray, Sergio G., Talluri, V.S.S.L.P., Sudhakaran, Deepa P., Gan, Hui T., Gardenö, Dániel, Friess, Karel, Castro Neto, Antonio H.
• Format: Article
• Language: English
• ISSN: 0360-3199
• DOI: 10.1016/j.ijhydene.2024.09.435

Hydrogen gas (H2) is a promising energy carrier capable of replacing fossil fuels and achieving net zero emissions. However, purifying H2 for applications like fuel cells and industrial processes is challenging due to impurities affecting performance. Two-dimensional (2D) materials, particularly graphene-based membranes, are promising for H2 purification due to their unique properties. The hydrogen (H2) permeation capability of graphene-based membranes is particularly significant. This study examines the use of commercial and cost-effective graphene oxide (GO) to fabricate multilayer graphene membranes, focusing on the impact of membrane thickness on H2 and CO2 separation. By using a scalable vacuum filtration method to coat porous ceramic substrates, membranes with controlled thicknesses were produced and characterised using AFM, FESEM, XRD, and gas permeation measurements. The study identified an optimal membrane thickness range (4 nm–250 nm) and the GO quantity (0.44 μg/cm2 to 1.76 μg/cm2) needed for effective H2/CO2 separation. This research aims to guide the development of cost-effective, mass-produced 2D-based membranes for industrial H2 purification. [Display omitted] •2D materials and graphene-based membranes are notable for their H2 permeability.•GO membrane thickness 4–250 nm and quantity 0.44–1.76 μg/cm2 for H2/CO2 separation.•Permeance and selectivity as a function of the thickness of GO membranes.•Average commercial GO and scalable methods: potential high-permeability membranes.•Industrial requirements of high permeability and scalability: graphene's potential.