Construction of bifunctional vertical nanochannels in GOM with swift heavy ion irradiation for enhancing the stability and nanofiltration performance

Graphene oxide membrane (GOM) shows great advantages in nanofiltration with the hydrophilicity and the tunable two-dimensional nanochannels. However, the instability in solution hinders the further utilization of GOM in nanofiltration. Therefore, we presented a method to improve the stability and permeability by constructing vertical channels using swift heavy ion (SHI) irradiation. In this work, the XPS, FT-IR and TEM results revealed that the SHI irradiation not only creates more shortcuts for water permeation but also stabilizes the twodimensional nanochannels by local GO reduction. Meanwhile, the XRD results indicated the increased rejection of GOM was attributed to the reduction of GO layer spacing. Consequently, the bifunctional vertical channels were obtained to enhance the stability and nanofiltration performance, which may provide a new strategy for the preparation of GOM.

Automated summary

Graphene oxide membrane (GOM) has hydrophilicity and tunable two-dimensional nanochannels, but its instability in solution limits its application in nanofiltration. In this study, we proposed a method to improve the stability and permeability of GOM by constructing vertical channels using swift heavy ion (SHI) irradiation. The results showed that SHI irradiation not only created shortcuts for water permeation but also stabilized the nanochannels by reducing graphene oxide (GO). Furthermore, the rejection of GOM increased due to the reduction of GO layer spacing. Therefore, the bifunctional vertical channels enhanced the stability and nanofiltration performance, providing a new strategy for GOM preparation.