Electronic-level deciphering of the desalination mechanism of high- performance graphenylene membranes

K Meng and YT Niu and JJ Xu and YX Ma and CH Zhang and S Ming and XH Yu and J Rong and HY Hou, JOURNAL OF MEMBRANE SCIENCE, 664, 121068 (2022).

DOI: 10.1016/j.memsci.2022.121068

The insufficiency of available freshwater has surged as a major global concern in recent years, and the issue is raising ever more awareness. Meanwhile, the recent experimental synthesis of graphenylene has inspired researchers to pursue its applicative merits. The related properties regarding lithium-ion storage electrodes and gas separation membranes of graphenylene have been reported. However, the suitability of graphenylene as a desalination membrane has yet to be fully established. In the present study, with a view to delineating the action mechanism of graphenylene desalination membrane, we have dissected its structure and properties through firstprinciples and molecular dynamics. The results illustrate that graphenylene comprising dodecagonal, hexagonal, and tetragonal carbon rings contains 0.55 nm nanopores, which should permit outstanding desalination properties. In addition, the periodic pore distribution should support stress dispersion in service to preserve membrane integrity. The low water-molecule free-energy barrier, remarkable salt ion adsorption properties, and favorable anti- agglomeration ability endow graphenylene with desirable permeability and selectivity. Furthermore, we demonstrate that graphenylene is a 2D Dirac semi-metallic material. The interlinked electronic structure of which confers it with self-cleaning behavior, facilitating the restoration of water flux. The present research has elucidated the mechanism whereby effective desalination may be achieved on graphenylene membranes. Further, it has clarified the potential applicability of such membranes. They show good prospects for the advancement of seawater desalination technology.

Return to Publications page