Functionalized graphene oxide-based lamellar membranes for organic solvent nanofiltration applications

In this study, two-dimensional graphene oxide-based novel membranes were fabricated by modifying the surface of graphene oxide nanosheets with six-armed poly(ethylene glycol) (PEG) at room conditions. The as-modified PEGylated graphene oxide (PGO) membranes with unique layered structures and large interlayer spacing (similar to 1.12 nm) were utilized for organic solvent nanofiltration applications. The as-prepared 350 nm-thick PGO membrane offers a superior separation (>99%) against evans blue, methylene blue and rhodamine B dyes along with high methanol permeance similar to 155 +/- 10 L m(-2) h(-1), which is 10-100 times high compared to pristine GO membranes. Additionally, these membranes are stable for up to 20 days in organic solvent. Hence the results suggested that the as-synthesized PGO membranes with superior separation efficiency for dye molecules in organic solvent can be used in future for organic solvent nanofiltration application.

Automated summary

In this study, two-dimensional graphene oxide-based membranes were fabricated by surface modification of graphene oxide with six-armed poly(ethylene glycol) (PEG) at room temperature. The as-modified PEGylated graphene oxide (PGO) membranes showed unique layered structures and large interlayer spacing, which made them suitable for organic solvent nanofiltration. The prepared PGO membrane exhibited superior separation efficiency (>99%) for several dye molecules and had high methanol permeance (155 +/-10 L m(-2) h(-1)), which was 10-100 times higher than pristine GO membranes. The PGO membranes also showed stability for up to 20 days in organic solvent. Therefore, these results suggest that the synthesized PGO membranes with superior separation efficiency can be used for organic solvent nanofiltration in the future.