Dynamically Gas‐Phase Switchable Super(de)wetting States by Reversible Amphiphilic Functionalization: A Powerful Approach for Smart Fluid Gating Membranes. (16th November 2017)

• Record Type: Journal Article
• Authors: Wong, William S. Y.; Gengenbach, Thomas; Nguyen, Hieu T.; Gao, Xiang; Craig, Vincent S. J.; Tricoli, Antonio
• Is Part Of: Advanced functional materials. Volume 28:Number 2(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-11-16
• Subjects: amphiphiles -- fluid gating -- gas‐phase triggers -- self‐assembly -- switchable super(de)wetting; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.201704423
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: In nature, cellular membranes perform critical functions such as endocytosis and exocytosis through smart fluid gating processes mediated by nonspecific amphiphilic interactions. Despite considerable progress, artificial fluid gating membranes still rely on laborious stimuli‐responsive mechanisms and triggering systems. In this study, a room temperature gas‐phase approach is presented for dynamically switching a porous material from a superhydrophobic to a superhydrophilic wetting state and back. This is realized by the reversible attachment of bipolar amphiphiles, which promote surface wetting. Application of this reversible amphiphilic functionalization to an impermeable nanofibrous membrane induces a temporary state of superhydrophilicity resulting in its pressure‐less permeation. This mechanism allows for rapid smart fluid gating processes that can be triggered at room temperature by variations in the environment of the membrane. Owing to the universal adsorption of volatile amphiphiles on surfaces, this approach is applicable to a broad range of materials and geometries enabling facile fabrication of valve‐less flow systems, fluid‐erasable microfluidic arrays, and sophisticated microfluidic designs. Abstract : Inspired by the spontaneous self‐­assembly of simple amphiphilic hydro­carbons, a reversible amphiphilic functionalization concept for porous hierarchical material is presented. The gas‐phase tuning of wettability for membranes is demonstrated, achieving cycles of superhydrophilicity and near‐superhydrophobicity. Potential of the concept is showcased through valve‐less fluid‐gating and erasable microfluidic templates.