Bio-enabled syntheses of functional mineral oxide thin films

Li, Yihong

Title:

Bio-enabled syntheses of functional mineral oxide thin films

dc.contributor.advisor	Sandhage, Kenneth H.
dc.contributor.author	Li, Yihong
dc.contributor.committeeMember	Barefield, Edward Kent
dc.contributor.committeeMember	Bucknall, David
dc.contributor.department	Materials Science and Engineering
dc.date.accessioned	2015-01-12T20:29:02Z
dc.date.available	2015-01-13T06:30:04Z
dc.date.created	2013-12
dc.date.issued	2013-11-21
dc.date.submitted	December 2013
dc.date.updated	2015-01-12T20:29:02Z
dc.description.abstract	The bio-enabled syntheses of functional nano-structured metal oxide thin films is of importance for a range of applications, in photonics, electronics, sensing, cell engineering, and biochemical devices. This type of novel syntheses method can overcome problems common in conventional oxide processing. In general, conventional oxide processes often require thermal treatment, caustic chemicals, and mechanical processing when producing shape-controlled inorganic materials. In contrast, biological processes are usually carried out under mild conditions (low temperature, neutral pH, and atmospheric pressure) and are therefore promising for the development of benign processes. Functional materials synthesized at room temperature using biomolecules are promising due to their expediency. During recent years, significant discoveries and progress have been made in discovering, and finding new applications for such biomimetic oxide-based minerals. However, much of the research has focused on SiO- and TiO-bearing organic-inorganic hybrid materials, of which a significant limitation is that, there are relatively few water-soluble inorganic oxide precursors commercially available for such biological syntheses. Two common compounds that are used in the biomimetic syntheses of SiO₂ and TiO₂ are tetramethoxisilane (TMOS) and Ti(IV) -bis(ammonium lactato) dihydroxide ( TiBALDH ). As a result, approaches to synthesize new water-soluble transitional metal complexes for use as precursors in the biomineralization of the corresponding functional metal oxide thin films were explored in this work, in order to expand the range of functional oxide chemistries formed via bio-enabled methods. A Ti-containing compound was synthesized to compare the behavior of commercially-available and as-synthesized TiBALDH. Another titanium-containing complex with citrate ligands, instead of lactate, was also synthesized to investigate the influence of the ligand type on the deposition behavior of the precursors. Zirconium- and hafnium-containing complexes were also synthesized to demonstrate the feasibility and versatility of the idea of applying bio-enabled syntheses to the fabrication of functional mineral oxides other than the reported SiO₂ and TiO₂. The second part of this thesis focuses on developing a novel way to fabricate porous functional mineral oxide thin films with controlled pore size, which can be used in a variety of applications, such as dye loading for optical, photochemical, or electrochemical purposes. Commercially-available, carboxyl-group-terminated polystyrene spheres of different sizes were utilized as pore-size controllers in the bio-enabled syntheses of TiO₂ by protamine. This approach has been found to be an effective means of creating uniform pores in inorganic mineral oxide coatings. The accomplishments of this work have the potential to be integrated so as to expand the boundaries of biomineralization in materials science and engineering fields.
dc.description.degree	M.S.
dc.embargo.terms	2014-12-01
dc.format.mimetype	application/pdf
dc.identifier.uri	http://hdl.handle.net/1853/52955
dc.language.iso	en_US
dc.publisher	Georgia Institute of Technology
dc.subject	Bio-enabled
dc.subject	Layer-by-layer
dc.subject	Complex
dc.subject	Thin film
dc.subject	TiO₂
dc.subject	ZrO₂
dc.subject	HfO₂
dc.subject	Protamine
dc.title	Bio-enabled syntheses of functional mineral oxide thin films
dc.type	Text
dc.type.genre	Thesis
dspace.entity.type	Publication
local.contributor.corporatename	School of Materials Science and Engineering
local.contributor.corporatename	College of Engineering
relation.isOrgUnitOfPublication	21b5a45b-0b8a-4b69-a36b-6556f8426a35
relation.isOrgUnitOfPublication	7c022d60-21d5-497c-b552-95e489a06569
thesis.degree.level	Masters