A self-cleaning membrane based on NG/g-C3N4 and graphene oxide with enhanced nanofiltration performance

A vacuum filtration method was used to fabricate a membrane based on graphene oxide (GO), N-doped graphene (NG) and g-C 3 N 4 nanosheets on a commercial substrate. In the composite membrane (GO/NG/g-C 3 N 4 membrane) NG/g-C 3 N 4 was employed as a photocatalytic nanomaterial and intercalated into GO, while maintaining the unique laminar structure of GO-based membranes. Characterization and the results of several membrane separation tests showed that the NG/g-C 3 N 4 nanosheet was synthesized successfully and the GO/NG/g-C 3 N 4 membrane possessed excellent hydrophilicity, flux, and dye rejection performance. The flux of the GO/NG/g-C 3 N 4 membrane reached 7.93 L m −2 h −1 bar −1 , which was 3 times higher than that of the pure GO membrane. In addition, the rejection of various dyes, including methylene blue (MB), Congo red (CR), rhodamine B (RhB), crystal violet (CV), and eriochrome black T (EBT), reached over 90%. Above all, the NG/g-C 3 N 4 membrane endowed the GO/NG/g-C 3 N 4 composite membrane with photocatalytic activity for the efficient removal of organic dyes from polluted water, and the composite membrane could be used for long-term nanofiltration because of its self-cleaning ability. This study provides a photocatalytic graphene oxide-based membrane for enhanced water purification.