Taming Self-Organization Dynamics to Dramatically Control Porous Architectures
Sader, John E
Boland, John J
American Chemical Society
MetadataShow full item record
Daly, R., Sader, J. E., & Boland, J. J. (2016). Taming Self-Organization Dynamics to Dramatically Control Porous Architectures. ACS Nano, 10 3087-3092. https://doi.org/10.1021/acsnano.5b06082
We demonstrate templating of functional materials with unexpected and intricate micro- and nanostructures by controlling the condensation, packing, and evaporation of water droplets on a polymer solution. Spontaneous evaporation of a polymer solution induces cooling of the liquid surface and water microdroplet condensation from the ambient vapor. These droplets pack together and act as a template to imprint an entangled polymer film. This breath figure (BF) phenomenon is an example of self-organization that involves the long-range ordering of droplets. Equilibrium-based analysis provides many insights into contact angles and drop stability of individual drops, but the BF phenomenon remains poorly understood thus far, preventing translation to real applications. Here we investigate the dynamics of this phenomenon to separate out the competing influences and then introduce a modulation scheme to ultimately manipulate the water vapor− liquid equilibrium independently from the solvent evaporation. This approach to BF control provides insights into the mechanism, a rationale for microstructure design, and evidence for the benefits of dynamical control of self-organization systems. We finally present dramatically different porous architectures from this approach reminiscent of microscale Petri dishes, conical flasks, and test tubes.
self-organization, breath figures, non-coalescence, water droplet, soft lithography, honeycomb
The financial support of Science Foundation Ireland (Grant No. 06/IN.1/I106) and the Australian Research Council grants scheme are gratefully acknowledged.
External DOI: https://doi.org/10.1021/acsnano.5b06082
This record's URL: https://www.repository.cam.ac.uk/handle/1810/253642