Theoretical Prediction of Mechanical Strength and Desalination Performance of One-Atom-Thick Hydrocarbon Polymer in Pressure-Driven Separation

Abstract

One-atom-thick materials hold promise for the future of membrane-based gas purification and water filtration applications. However, there are a few investigations on the mechanical properties of these materials under pressure-driven condition. Here, by employing molecular simulation techniques and continuum mechanics simulation, we investigate the mechanical strength of two-dimensional hydrocarbon polymers containing sub-nanometer pores with various topologies. We demonstrate that the mechanical strengths of the membranes are correlated with their pore sizes and geometries. In addition, when the pore size of substrates is controlled within a reasonable range, all of the membrane candidates can withstand the practical hydraulic pressure of few megapascal. The studied materials also exhibit better seawater desalination performance as compared to the traditional polymeric reverse osmosis membrane. This work presents a new route to design new separation membrane, and also propose a simulation method to evaluate the mechanical strength and desalination performance.

Towards the realisation of high permi-selective MoS2 membrane for water desalination

“…However, the inherent properties of MoS 2 with regards to its ability to preserve its mechanical integrity under extreme hydraulic pressures in a reverse osmosis RO desalination process needs to be explored. Mechanical strengths of the membranes correlate with their pore sizes and geometries 164 . While the presence of water has been observed to reduce the fracture toughness of some materials like oxide ceramics, it has also been observed to improve the fracture toughness of materials such as dentine 165 .…”