| Fabrication of Nanostructured TiO2 Fibers on TiO2 Coatings Produced from a Nanostructured Feedstock | ||
| Dr. Rogerio S. Lima1, B. R. Marple1, H. Lee2 and Prof Sheikh A. Akbar3, 1National Research Council of Canada, 75 de Mortagne Blvd., Boucherville, QC J4B 6Y4, Canada, 2Department of Materials Science and Engineering, Ohio State University, 2041 College Road, Columbus, OH 43210, 3NSF Center for Industrial Sensors and Measurements (CISM), The Ohio State University, Department of Materials Science and Engineering, Columbus, OH 45422
Titania (TiO2) coatings were produced using the high velocity oxy-fuel (HVOF) technique on Ti-6Al-4V substrates. The titania feedstock powder exhibited nanostructured morphology, formed by a successive agglomeration of individual nanostructured titania particles (spray-drying) smaller than 100 nm. The resulting coatings were dense (porosity <1%) and exhibited rutile and anatase as phases with percentages of ~75% and ~25%, respectively. These coatings were heat-treated in a H2/N2 environment at 700oC for 8h. During the heat-treatment nanostructured titania fibers were formed on specific surface regions of the coatings. The nanofibers formed by this “chemical or reaction-based texturing” exhibited diameters of 50-200 nm and lengths in the order to 1-10 mm. It is thought that engineering these surfaces at nano and micro-scales may lead to interesting applications of titania coatings related to (i) cell attachment/growth (for biomedical applications) and (ii) photocatalytic properties. The possible mechanisms of nanofiber formation are discussed. | ||