A sophisticated design to turn saltwater into freshwater
Scientists have developed an improved type of membrane for desalinating water. By controlling the evolution of the structures of the membrane, researchers were able to boost the water flux of a membrane by five-fold. The advancement also demonstrates one of Alan Turing's greatest contributions to science. In 1952, just two years before he died, Alan Turing published his only chemistry paper. He theorized that by including chemicals that both activate and inhibit a reaction, under certain conditions diffusion during the reaction process will generate molecular structures at specifically spaced distances from one another. Putting this theory into practice more than 60 years later, Zhe Tan and colleagues created spotted and striped Turing structures to make permeable membranes that dramatically boost its ability to purify water. Tests reveal that the system exhibits excellent water-salt separation ability, surpassing that of traditional nanofiltration membranes. The authors note that, whereas traditional polymer membranes involve a tradeoff where higher water permeability invariably leads to lower water-salt selectivity, their new system has both high water permeability and water-salt selectivity.