Photocatalytic interlayer spacing adjustment of a graphene oxide/zinc oxide hybrid membrane for efficient water filtration

• Published in: Desalination 2020-02, Vol.475, p.114174, Article 114174
• Main Authors: Hassanpour, Amir, Nahar, Sharifun, Tong, Xin, Zhang, Gaixia, Gauthier, Marc A., Sun, Shuhui
• Format: Article
• Language: English
• Subjects: GO interlayer spacing adjustment; GO nano-channel compaction; GO photocatalytic reduction; Graphene oxide/zinc oxide composite membrane; ZnO nanoparticles
• ISSN: 0011-9164; 1873-4464
• DOI: 10.1016/j.desal.2019.114174

The intercalation of ZnO nanoparticles into a layer-stacked graphene oxide membrane has a positive impact on its water permeability, physical compaction, and antifouling properties. The interlayer spacing within the GO/ZnO composite membrane is adjustable to a high degree of precision (down to 0.04 Å) by ultra-violet irradiation. This is the smallest controlled reduction of interlayer spacing within a GO membrane ever reported. The photocatalytic reduction of the composite membranes was characterized by their X-ray photoelectron and Raman spectra. The results of the biocidal tests show that the addition of ZnO nanoparticles to a GO membrane inhibits the growth of Escherichia coli B bacteria. The rate of water permeation through the ZnO/GO composite membrane is five times higher than for a pristine GO membrane. The nano-channels in the GO membrane remain locally unchanged after the addition of the ZnO nanoparticles. Thus, the incorporation of the ZnO nanoparticles into the GO membrane has no/little (1% reduction) effect on its Rhodamine B rejection performance. In addition, the presence of ZnO nanoparticles in the nano-channels reduces the extent of membrane compaction, which would decrease the cost of filtration. [Display omitted] •ZnO nanoparticles were synthesized in-situ within a GO dispersion at room temperature•Interlayer spacing of the GO/ZnO composite membrane was adjusted to a high degree of precision by UV irradiation•Antibacterial properties of a GO membrane increased by addition of ZnO nanoparticles•GO/ZnO membranes showed five times higher water permeability with similar rejection performance to a pristine GO membrane•Intercalation of the ZnO nanoparticles into a GO membrane reduced the extent of membrane compaction