May 12, 2024

A New, Better Way to Desalinate Water

Utilizing chemical vapor deposition, Yu Han, Vincent Tung, Ingo Pinnau, and Lance Li, a former researcher at KAUST who is now connected with the University of Hong Kong, have actually established a method that helps control the growth of two-dimensional conjugated polymer structures into ultrathin carbon films.
Research scientist Yichen Cai and the group are now dealing with improving the antifouling property, mechanical strength, and long-lasting chemical stability of the membrane for future useful applications. Credit: 2022 KAUST; Anastasia Serin
The researchers deposited the monomer triethynylbenzene on atomically flat single-crystalline copper substrates in the presence of an organic base that acts as a driver. Triethynylbenzene bears three reactive groups that serve as anchor points for additional monomers. These groups reveal a 120-degree angle with regard to each other, creating arranged arrays of well-defined cyclic structures that stack into subnanometer-sized rhombic hydrophobic channels.
The membrane displayed excellent water desalination performance in forward and reverse osmosis configurations, exceeding those containing innovative materials such as carbon nanotubes and graphene. It also showed strong rejection for divalent ions, as well as small charged and neutral molecules.
Postdoc Jie Shen was the first author of the paper, published in Nature Materials. Credit: 2022 KAUST; Anastasia Serin
The scientists discovered that the water molecules formed a three-dimensional network inside the membrane rather of moving through the membrane along vertical triangular channels as one-dimensional chains. This discusses the fast water transportation through the membrane. “This unanticipated result revealed that the seemingly discrete vertical channels are actually interconnected by brief horizontal channels that can be easily neglected in the forecasted structural design,” Han says.
The team is now working on enhancing the antifouling residential or commercial property, mechanical strength, and long-term chemical stability of the membrane for future practical applications. They are also tweak its surface-charge properties and channel sizes. “Our ultimate objective is to provide a flexible multifunctional platform that satisfies the requirements of numerous applications, such as ion sieving, single-molecule sensing, and neural interfaces,” Han says.
Reference: “Fast water transport and molecular sieving through ultrathin bought conjugated-polymer-framework membranes” by Jie Shen, Yichen Cai, Chenhui Zhang, Wan Wei, Cailing Chen, Lingmei Liu, Kuiwei Yang, Yinchang Ma, Yingge Wang, Chien-Chih Tseng, Jui-Han Fu, Xinglong Dong, Jiaqiang Li, Xi-Xiang Zhang, Lain-Jong Li, Jianwen Jiang, Ingo Pinnau, Vincent Tung, and Yu Han, 8 August 2022, Nature Materials.DOI: 10.1038/ s41563-022-01325-y.

The researchers created brand-new more effective membranes for water desalination.
Unique membranes can remove salt from water.
A team led by King Abdullah University of Science & & Technology (KAUST) has actually demonstrated how ultrathin polymer-based ordered membranes can effectively remove salt from brine and seawater, providing a potential alternative for existing desalination systems.
” Water desalination membranes must simultaneously exhibit high water flux and high salt rejection,” states Yu Han, who led the study. Carbon nanomaterials, such as carbon nanotubes and graphene, are predicted to match these requirements since of their unique surface chemistry and tendency to stack into channels with diameters less than one nanometer. However, the obstacles of channel positioning and stacking avoid their large-scale usage in membranes.
KAUST scientists have developed a membrane (imagined above) with exceptional water desalination performance in forward and reverse osmosis configurations. Credit: 2022 KAUST; Anastasia Serin
” One method to attend to these restrictions is through two-dimensional permeable carbonaceous membranes with routine and uniformly dispersed subnanometer-sized molecular transport channels,” says first author Jie Shen, a postdoc in Hans group. Nevertheless, these membranes are typically synthesized in option, which promotes the random development of a disordered three-dimensional structure with badly defined micropores.

” Water desalination membranes need to at the same time display high water flux and high salt rejection,” says Yu Han, who led the study. The obstacles of channel positioning and stacking avoid their large-scale usage in membranes.
The scientists discovered that the water molecules formed a three-dimensional network inside the membrane rather of moving through the membrane along vertical triangular channels as one-dimensional chains. This describes the quick water transportation through the membrane. The team is now working on enhancing the antifouling home, mechanical strength, and long-term chemical stability of the membrane for future practical applications.