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198283 https://hdl.handle.net/2286/R.2.N.198283 http://rightsstatements.org/vocab/InC/1.0/ All Rights Reserved 2024 213 pages Doctoral Dissertation Academic theses Text eng Nguyen, Tam Le Phuong Seo, Dong-Kyun DK Birkel, Christina CS Hwa, Yoon Y Arizona State University Partial requirement for: Ph.D., Arizona State University, 2024 Field of study: Chemistry Syntheses of titanium dioxide and titanates in nonaqueous media have significant advantages over the traditional aqueous syntheses due to more controllable reaction conditions by avoiding fast hydrolysis and condensation of the precursors. This area of research is still in its infancy, mainly due to the lack of proper titanium precursors. Discovery of new precursors that are easily accessible and cost-effective is important not only for the advances in research, but also novel industrial applications of titanium dioxide and titanate compounds.Herein, new potential of titanyl sulfate dihydrate (TiOSO4·2H2O, “TSD”), an important intermediate in the Sulfate process, is recognized through its nonaqueous chemistry toward developments of new synthetic methodologies. Included in this thesis is a report on an exfoliative dissolution method designed specifically to exploit the Brønsted acidity and one-dimensional structure of TSD. TSD is found to be highly soluble in various polar organic solvents, such as methanol, amides, and dimethyl sulfoxide. Unlike the conventional dissociative dissolution processes, extensive analyses on the solutions and precipitates have proven that the dissolved species, particularly in methanolic solutions, stay as the one-dimensional chains after dissolution. The new chemistry was used for the synthesis of new organic-inorganic hybrids and polymer blends, the latter of which led to hierarchical and transparent titania upon calcination. With the methanolic TSD solutions, a new nonaqueous synthetic route for titanium dioxide-based nanomaterials were developed, through neutralization reactions of acidic TSD-MeOH solutions with inorganic bases. The use of basic salts, for example, calcite (CaCO3), resulted in the production and functionalization of calcium sulfate-hydrous titanium oxide hybrid nanofibers, all in a sustainable, one-pot and scalable process. Lastly, the methanolic TSD solution was utilized to design and develop a facile synthetic route for a new solid acid catalyst, TiOSO4@SiO2, that is, anhydrous TiOSO4 coating in the internal surface of aerogel-like porous silica. The new scalable method employed the polymeric TSD solution as both the precursor for TiOSO4 and the gluing agent without a supercritical drying step, showcasing the advantages of the nonaqueous chemistry of TSD over its aqueous chemistry in which the TSD cannot maintain its polymeric nature. Chemistry Materials Science aerogel-like materials Exfoliation functionalization low-temperature synthesis titania Titanyl sulfate dihydrate New Titanium Precursor From The Nonaqueous Chemistry Of Titanyl Sulfate Dihydrate