This study aimed at the identification of phase evolution in a particular polymorphic compound, Co-TiO2 (Cobalt doped Titania). Through the examination of the thermal stability of this nanomaterial, its morphological features and microstructural characteristics were evaluated and correlated with time exposed at high temperatures (room temperature to 800oC). Viable uses for the researched material include gas sensors, membranes, and optical coatings, making the findings of this research important to a number of high-tech industries. At the Advanced Material Characterization Laboratory, powder samples of Titania (Titanium Oxide - TiO2) prepared by sol-gel processing techniques, were used. Potential phases include Anatase, Brookite, and Rutile, coupled with phases of Cobalt Oxide. Electron and x- rays were used for precise identification of the unique crystal structure. Diffraction patterns of Titania samples were obtained, collected, and studied. Analysis of these diffraction patterns i.e. d-spacing (Angstroms) measurements was completed. Results were compared with published data in the JCPDS (Joint Committee on Powder Diffraction Standards) database and Pearson's Handbook of Crystallographic Data. In addition, computer simulations of diffraction patterns were also used to compare the experimentally obtained data with the theoretical results. At room temperature, the Titania system was generally consistent of the Anatase phase. As temperatures increased, Rutile gradually became the principal phase, ultimately remaining as the only phase evident. There was no indication of the existence of CoO (Cobalt Oxide) at any temperature. These findings hold important implications for the thermal stability of this nanomaterial.

This work was funded by Simons Grant 265210 and through the MRSEC for Thermal Spray Research (NSF Grant DMR0080021).