Nonuniform Material Deposition on Multi-Scale Textured Surfaces

Machado, Christian

doi:https://doi.org/10.21985/n2-taj8-4821

Work

Nonuniform Material Deposition on Multi-Scale Textured Surfaces

Public

Download PDF

Download All Files (.zip)

As opposed to the nanoscale deposition techniques often used for material syntheses, here, I focus on mesoscale material depositions and how to design interfaces to efficiently manage such deposition and potential accumulation. These deposition processes include condensation, condensation frosting, particle capture, and vaporization. Through the lens of energy and sustainability, this dissertation is primarily concerned with the careful and robust design of interfaces to generate unique behaviors that are largely resilient to different stimuli, as opposed to the generally fragile structures that aim at controlling wetting phenomena. Starting from the fundamental frameworks of heat and mass transfer and nucleation theory, I outline mechanics-based approaches to designing surfaces that resist frost formation, that enhance liquid collection via condensation and/or fog collection, and that address vaporization-induced surface fouling. All these design approaches start with a similar premise: inducing asymmetric material deposition. There are multiple ways this can be accomplished. First, the surfaces can be designed to focus and suppress mass transfer, either via diffusion flux or forced airflows, and the surfaces can be designed to focus where nucleation occurs, by creating patterns of surface energies. Rather than demonstrating that this can merely be done, I, instead, focus on how the implications of this non-uniform deposition and accumulation can be realized to promote energy-efficient applications. Simultaneously, these designs become more robust and easier to manufacture than the common photolithographic nanotexturing that most common alternative approaches employ. In full, I argue that an understanding of the mechanics surrounding an interface is equally important as the interface itself, and careful interfacial design should incorporate this understanding to generate new performance capabilities and unlock some of the challenges associated with addressing climate change.

Creator