Graphene Oxide Composite Membranes for water treatment

Graphene oxide (GO) membranes are outstanding candidates for water treatment thanks to the fast water permeation through two-dimensional nanocapillaries, combined with size and electrostatic ion exclusion mechanisms [1]. However, their use for aqueous separations processes is limited due to swelling phenomena, which reduce both the selectivity and mechanical stability of GO laminates. In the framework of the project IDEA [2] researchers from ITM-CNR are actively working on the design and development of high performing "green" GO membranes. Moreover, modelling studies are in progress with the aim to investigate graphene GO-polymer and GO-water interfaces interactions at the atomic and molecular scales (Figure 1). Our results validate an easily scalable method with a low environmental impact to produce GO supported on functionalized polymeric support exhibiting an excellent stability in water and saline solutions [3]. The experimental results highlight the key role of support chemistry, surface charge and topography to obtain composite membranes free from swelling or delamination issues. The composite GO membranes developed represent a further step ahead toward the large-scale application of GO-based membranes in separation processes. References [1] Nair, R. R.; Wu, H. A., Jayaram, P. N.; Grigorieva, I. V.; Geim, A. K. Unimpeded permeation of water through helium-leak-tight graphene-based membranes. Science 2012, 335, 442-444. [2] http://www.idea-eranetmed.eu/ [3] E. Fontananova et al. Submitted Acknowledgements This work was partially supported by the Italian Ministry of Education University and Research (prot. MIUR no. 10912, 06/06/2016; concession grant decree no. 3366, 12/18/2018) and the Deanship of Scientific Research at The University of Jordan within the project "Development of a solar powered, zero liquid discharge Integrated desalination membrane system to address the needs for water of the Mediterranean region", (IDEA-ERANETMED2-72-357)