Theses and Dissertations at Montana State University (MSU)
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Item Photonic applications of functionalized gold nanorods: progress towards nonlinear metamaterials(Montana State University - Bozeman, College of Letters & Science, 2016) Latterman, Ryan Eric Michael; Chairperson, Graduate Committee: Robert Walker; This dissertation contains one article of which Ryan Eric Michael Latterman is not the main author.Nonlinear processes are used to convert one color of laser light into another and are very useful to any research who needs multiple colors of light for basic research or commercial purposes. However, nonlinear processes are inherently very weak and require high input energy to utilize them. Using modeling, it was predicted that ordered arrays of gold nanorods (GNRs), acting as a metamaterial, could be used to fabricate a material that would exhibit field enhancement. Because nonlinear processes depend on the strength of the field in which they interact, enhancing the field strength while using the same amount of input power would make these processes much more efficient and useful. Progress towards these materials included the synthesis of GNRs and gold reactive polymers. These polymers were used to solubilize GNRs in organic solvents while also introducing attachment points for nonlinear chromophores. To study a material which resembled the one in our modeling predictions, flat gold and two dimensional arrays of gold nanopillars were functionalized with gold-reactive nonlinear organic chromophores and studied using sum frequency generation. It was found that flat gold samples functionalized with a nonlinear chromophore exhibited a tremendous SFG signal, but only in one input polarization configuration. However, gold nanopillar samples exhibited a significant SFG signal in both PPP and SSP polarization configurations. These data agree with our modeling results and indicate that the materials produced here have the potential to be used as a mirror-less optical parametric oscillator. Organic-soluble GNRs produced in this thesis were then used in an adjacent project to improve the efficiency of a diode-pumped solid state laser design. Nd:YAG lasers are routinely used to produced 1064 nm light by pumping at 808 nm with a semi-conductor diode laser. However, when 1064 nm light is reflected back into the laser cavity, a parasitic phenomenon called amplified spontaneous emission (ASE) occurs. ASE can be combatted by applying a material to the laser rod that absorbs at 1064 nm. GNRs were synthesized at a specific size to absorb at 1064 nm, solubilized in epoxy and applied to a Nd:YAG laser, increasing efficiency by almost two fold.Item Development of protein nanoparticle based composite materials(Montana State University - Bozeman, College of Letters & Science, 2013) Lucon, Janice Elizabeth; Chairperson, Graduate Committee: Trevor Douglas; Md Joynal Abedin, Masaki Uchida, Lars Liepold, Craig C. Jolley, Mark Young, and Trevor Douglas were co-authors of the article, 'A click chemistry based coordination polymer inside small heat shock protein' in the journal 'Chemical communications' which is contained within this thesis.; Shefah Qazi, Masaki Uchida, Gregory J. Bedwell, Ben LaFrance, Peter E. Prevelige, Jr, and Trevor Douglas were co-authors of the article, 'Using the interior cavity of the P22 capsid for site-specific initiation of atom transfer radical polymerization with high density cargo loading' in the journal 'Nature chemistry' which is contained within this thesis.Inspired by the core-shell composite structures found in nature, a range of protein based composites have been developed. These materials were made using synthetic approaches, which utilized the native protein architecture as an initiation point and size constrained reaction vessel for the piecewise formation of the second material. In the first illustration of this approach, a protein-P t composite was formed, where the protein cage has been modified to include a metal binding moiety for improved synthesis of metallic P t nanoclusters, which were shown to be an active H 2 catalyst. This composite was analyzed by native mass spectrometry to determine the number of P t ions bound prior to mineralization and to measure the distribution of species after mineralization, which provided a unique view into the mineralization process. The second illustration was a material synthesized using the cage-like protein architecture as an internal guiding synthetic scaffold for the formation of a coordination polymer core inside the protein cage. The construction of this coordination polymer was unusual in that unlike normal coordination polymer synthesis, coordination of the metal preceded formation the ditopic ligands, which were afterwards completed using azide-alkyne click chemistry. Finally, a collection of protein-polymer composites were developed, which utilized a living radical polymerization method, atom transfer radical polymerization, to form internal polymer cores. By labeling one of these protein-polymer constructs with a Gd based MRI contrast agent a material with vastly improved relaxivity was made. The development of each of these three types of composites served to improve our understanding of the natural systems, from which they are derived, and provide a basis for further development of advanced multicomponent nanomaterials.