Graphene oxide membranes on ceramic hollow fibers – Microstructural stability and nanofiltration performance

• Graphene oxide membranes supported by ceramic hollow fibre are prepared.
• Drying-related shrinkage leads micro-structural instability in GO HF membranes.
• Storage of GO HF membranes in water avoids the stability problem.
• The GO HF membranes show promising nanofiltration performance.

Graphene oxide (GO) membranes have demonstrated great potential in liquid filtration. With the aim of real applications, GO membranes in a hollow fiber shape are of particular interest because of the high-efficiency and easy-assembly features at the module level. We report here that GO membranes on ceramic hollow fiber substrates are unstable at the dry state, mainly due to the drying-related shrinkage. And we demonstrate that these GO hollow fiber membranes can be stabilized by keeping them wet after initial controlled formation of the membranes. The GO hollow fiber membranes show higher permeation fluxes of acetone and methanol than most commercial membranes, and reject molecules larger than 300 Da, showing a great potential in the use of value-added organic solvent nanofiltration processes.