Multifunctional Materials: Bottom-Up and Top-Down

Citation

Weitekamp, Raymond Andrew (2015) Multifunctional Materials: Bottom-Up and Top-Down. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/Z90C4SSB. https://resolver.caltech.edu/CaltechTHESIS:06042015-140901217

Abstract

This thesis is thematically separated into two complimentary approaches to advanced materials synthesis: bottom-up and top-down. Part I will discuss the self-assembly of photonic crystals, a unique class of periodic nanostructured materials featuring resonant optical response. Chapter 1 will introduce the concepts of self-assembly, specifically in the context of colloidal crystals and block copolymer nanostructures. Chapter 2 summarizes many years of work towards the goal of utilizing brush block copolymers as paintable photonic crystals. We employed 2D colloidal crystals as resonant light-trapping elements to improve the performance of thin-film solar cells; this work is described in Chapter 3. Part II of the thesis is centered around the concept of functional lithography: the ability to directly pattern materials with tailored physical properties and chemically active interfaces. We will briefly provide a history of photolithography in Chapter 4, and outline some of the limitations of the incumbent lithographic methods. The discovery of latent reactivity in ruthenium vinyl ether complexes, and the subsequent development of PhotoLithographic Olefin Metathesis Polymerization (PLOMP), are discussed in Chapter 5. This discovery has since blossomed into a true platform technology. We will discuss improvements to the functional group tolerance of PLOMP, as well as a few of our efforts to use PLOMP towards specific applications in Chapter 6. In the final Chapter 7 we document our attempts to activate PLOMP resists via multiphoton absorption, towards 3D printing of chemically functional microstructures.

Thesis Files