Simon Gravelle
Universität Stuttgart, Institute for Computational Physics (ICP)
https://simongravelle.github.io/
“Unidirectional water valve in Tillandsia plant”
Tillandsia landbeckii is a rootless plant thriving in the hyper-arid Atacama Desert of Chile. These plants use unique cellulose-based microscopic structures called trichomes to collect fresh water from coastal fog. The trichomes rely on a passive mechanism to maintain an asymmetrical transport of water: they allow for the fast absorption of liquid water deposited by sporadic fog events while preventing evaporation during extended drought periods. We combined measurements performed on the plant with simulations to explain how a remarkable asymmetry in water conductance arises from a clever juxtaposition of a thick hygroscopic wall and a semipermeable membrane. We then fabricated an artificial composite membrane mimicking the trichome structure as a first step towards a bioinspired fog collector.