Solution and Solid-State Studies of DNA-Programmable Nanoparticle Single Crystals

This thesis lays the foundation for three main areas that have significantly advanced the field of DNA-programmable nanoparticle assembly: (1) the synthesis of nanoparticle superlattices with novel lattice symmetries (2) post-assembly characterization and applications of superlattices that have been transferred from solution to the solid state and (3) the realization of a slow-cooling strategy for synthesizing faceted nanoparticle single crystals. Together, these advances mark a turning point in the evolution of DNA-programmable assembly from a simple proof-of-concept demonstrated in 1996 to a powerful materials development strategy that has inspired many ongoing investigations in fields including catalysis, plasmonics, and electronics.;Chapter 1 begins with an overview of controlled crystallization and its importance across fields including chemistry and materials science. This followed by a description of DNA-programmable assembly and a discussion on its advantages as an assembly strategy. Chapter 2 describes a powerful strategy for synthesizing nanoparticle superlattices using a coreless nanoparticle consisting purely of spherically-oriented oligonucleotides. This "three dimensional spacer approach" allows for the synthesis of nanoparticle superlattices with exotic structures, including one with no mineral equivalent.;While DNA is a versatile ligand for nanoparticle assembly, the resulting superlattices are only stable in solution. Chapter 3 addresses these limitations and presents a method for transitioning these materials from solution to the solid state through silica encapsulation. This encapsulation process has transformed the ability to interrogate these materials using electron microscopy, and it has enabled all the studies in subsequent chapters of this thesis.;In Chapter 4, a slow-cooling crystallization technique is described that allows for the synthesis of single crystalline microcrystals with well-defined facets from DNA-nanoparticle building blocks. The ability to synthesize single crystals provides insight into nanoparticle crystallization processes, and it is crucial for ongoing studies on their incorporation into device applications.;The porosity and catalytic properties of silica-embedded DNA-nanoparticle superlattices are investigated in Chapter 5. A case is presented for the use of supported DNA-assembled nanoparticle superlattices as heterogeneous catalysts.;Finally, Chapter 6 provides an outlook on the promising future of DNA-programmable assembly ranging from synthesis to applications.