MEAM Seminar: “Micro/Nanomanufacturing of 3D Functional Coatings via Self-Limiting Electrospray Deposition”
November 26, 2019 at 10:30 AM - 12:00 PM
Organizer
Venue
Recent developments in nanostructured materials have demonstrated myriad desirable properties ranging from optical and mechanical metamaterials to biomanipulative surfaces. To bring these properties from the lab to the commercial space will require innovative nanomanufacturing strategies focused on scalable and cost-effective techniques. My lab, the Hybrid Micro/Nanomanufacturing Laboratory, applies the manipulation of fundamental driving forces to this challenge through combinations of top-down and bottom-up techniques for new hybrid lithographic strategies. In this seminar, I will highlight one such strategy: self-limiting electrospray deposition (SLED) of thin film microcoatings. Electrospray deposition is a well-established technique for the creation of thin films from the spray of highly charged droplets loaded with the materials to be deposited. In SLED, specific manipulation of the electrostatic repulsion, hydrodynamic forces, and evaporation kinetics can be employed to conformally cover 3D architectures with microcoatings. The generated coatings are hierarchical, possessing either nanoshell or nanowire microstructure. Having demonstrated the mechanism of the self-limiting effect, we have developed the ability to employ materials that would be otherwise incompatible with self-limiting. In this way we have incorporated a wide variety of functional systems, including: (1) biocompatible, (2) plasmonic, (3) elastomerically-toughened composite, (4) anti-corrosive epoxy or sol gel, and (5) electrically conductive coatings. We have also characterized the geometric limits of features that can be coated through this approach, showing that the 3D capabilities increase with decreasing feature size to the micron-scale. This property, combined with the hierarchical structure of the coatings, shifts the burden of micro/nanoscale resolution from a costly or slow technique to a more scalable method, thereby removing barriers for integration into advanced manufacturing techniques such as roll-to-roll or additive manufacturing.

