Spongy all-in-liquid materials by in-situ formation of emulsions at oil-water interfaces.

TitleSpongy all-in-liquid materials by in-situ formation of emulsions at oil-water interfaces.
Publication TypeJournal Article
Year of Publication2022
AuthorsBazazi, P, Stone, HA, S Hejazi, H
JournalNat Commun
Date Published2022/07/18
KeywordsEmulsions, Ink, Nanoparticles, Silicon Dioxide, Water

Printing a structured network of functionalized droplets in a liquid medium enables engineering collectives of living cells for functional purposes and promises enormous applications in processes ranging from energy storage to tissue engineering. Current approaches are limited to drop-by-drop printing or face limitations in reproducing the sophisticated internal features of a structured material and its interactions with the surrounding media. Here, we report a simple approach for creating stable liquid filaments of silica nanoparticle dispersions and use them as inks to print all-in-liquid materials that consist of a network of droplets. Silica nanoparticles stabilize liquid filaments at Weber numbers two orders of magnitude smaller than previously reported in liquid-liquid systems by rapidly producing a concentrated emulsion zone at the oil-water interface. We experimentally demonstrate the printed aqueous phase is emulsified in-situ; consequently, a 3D structure is achieved with flexible walls consisting of layered emulsions. The tube-like printed features have a spongy texture resembling miniaturized versions of "tube sponges" found in the oceans. A scaling analysis based on the interplay between hydrodynamics and emulsification kinetics reveals that filaments are formed when emulsions are generated and remain at the interface during the printing period. Stabilized filaments are utilized for printing liquid-based fluidic channels.

Alternate JournalNat Commun
PubMed ID35851272
PubMed Central IDPMC9293904
Grant List07186-2019 / / Gouvernement du Canada | Natural Sciences and Engineering Research Council of Canada (Conseil de Recherches en Sciences Naturelles et en Génie du Canada) /