Phys.org April 19, 2023
Two essential features of intelligent transport are the ability to adapt to different external and internal conditions and memorize the previous state. In biological systems, the most common form of such intelligence is expressed as hysteresis. Despite numerous advances made over previous decades on smart membranes, it remains a challenge to create a synthetic membrane with stable hysteretic behaviour for molecular transport. Researchers in the UK demonstrated the memory effects and stimuli-regulated transport of molecules through an intelligent, phase-changing MoS2 membrane in response to external pH. They showed that water and ion permeation through 1T′ MoS2 membranes follows a pH-dependent hysteresis with a permeation rate that switches by a few orders of magnitude. They established that this phenomenon is unique to the 1T′ phase of MoS2, due to the presence of surface charge and exchangeable ions on the surface. They also demonstrated the potential application of this phenomenon in autonomous wound infection monitoring and pH-dependent nanofiltration. According to the researchers their work deepens understanding of the mechanism of water transport at the nanoscale and opens an avenue for the development of intelligent membranes… read more. TECHNICAL ARTICLEÂ
Water permeation through MoS2 membranes. Credit: Nature (2023)