Controlling water evaporation through self-assembly

Research output: Contribution to journalArticle

Abstract

Water evaporation concerns all land-living organisms, as ambient air is dryer than their corresponding equilibrium humidity. Contrarily to plants, mammals are covered with a skin that not only hinders evaporation but also maintains its rate at a nearly constant value, independently of air humidity. Here, we show that simple amphiphiles/water systems reproduce this behavior, which suggests a common underlying mechanism originating from responding self-assembly structures. The composition and structure gradients arising from the evaporation process were characterized using optical microscopy, infrared microscopy, and smallangle X-ray scattering. We observed a thin and dry outer phase that responds to changes in air humidity by increasing its thickness as the air becomes dryer, which decreases its permeability to water, thus counterbalancing the increase in the evaporation driving force. This thin and dry outer phase therefore shields the systems from humidity variations. Such a feedback loop achieves a homeostatic regulation of water evaporation.

Details

Authors
Organisations
External organisations
  • University of Toulouse
  • Paul Scherrer Institute
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Physical Chemistry

Keywords

  • Cnrs, institut national polytechnique de toulouse, université Paul sabatier, Evaporation, Gradient, Homeostatic, Laboratoire de génie chimique, Regulation, Self-assembly, Université de toulouse
Original languageEnglish
Pages (from-to)10275-10280
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Volume113
Issue number37
Publication statusPublished - 2016 Sep 13
Publication categoryResearch
Peer-reviewedYes