September 2020
Vol 6, Issue 38

About The Cover

Cover image expansion

ONLINE COVER Clean water scarcity is one of this century's major global problems, with at least four billion people lacking access to water for at least one month out of each year and more than 350,000 children dying annually from waterborne diseases. While technologies exist to produce freshwater from seawater through desalination using reverse osmosis, these thin film composite membrane technologies are limited by trade-offs between the quality of the separation process and the rate at which water flows through the membrane. Narrow carbon nanotubes, which mimic the structure of channel proteins that facilitate water transport between cells, have been suggested as an alternative with both strong ion selectivity and speedy water transport rates. To better understand the potential of carbon nanotubes for this purpose, Li et al. performed experimental measurements and computer simulations of water and ion transport through a carbon nanotube with a 0.8 nanometer diameter. The researchers found that the tube effectively filtered out unwanted ions. Based on estimates of its real-world performance, they also showed that carbon nanotubes may be able to overcome the tradeoffs of thin film composite membrane technologies. [CREDIT: ELLA MARU STUDIO]