Fabrication of high-strength graphene oxide/carbon fiber nanocomposite membranes for hydrogen separation applications

Abstract

Graphene oxide (GO) is a promising nanosheet for developing next-generation thin-membrane technology to enhance gas permeability and selectivity performance based on the interlayer spacing principle. This study aimed to strengthen GO membranes for enhancing gas permeability and selectivity using non-woven carbon fiber (CF) fabric. The GO/CF membranes were synthesized with 1 wt% of GO and different CF orientations in the matrices with various GO layer thicknesses (200–800 µm). The resulting membranes were characterized for their surface and cross-sectional morphology, pore sizes, mechanical, chemical, and thermal analysis. The SEM results showed successful deposition of GO flakes onto the CF surface with high cohesion with the fibers, accompanied by some deviations in the GO edges, allowing gases to pass through the membranes. In addition, thinner membranes had higher Young's modulus (56 MPa) and surface roughness in the ranges of 84–184 nm. While the gas permeability measurements revealed that the thinner membranes (200 µm) had higher gas permeability in the range 7809214 Barrer (CO2) and 23154004 Barrer (H2) with an increase of 68–92% compared to the thicker membranes (600 and 800 µm). Moreover, thinner membranes showed higher selectivities about 5.2 (H2/CO2), 4.3 (H2/N2) and 3.6 (H2/CH4). Overall, these results indicate that GO/CF membranes are a promising solution for hydrogen separation due to their high strength and ease of fabrication.