Optimizing TiO2 Anatase Thin Film Growth for Photocatalysis
Gabriella Chavez
Department of Chemistry & Biochemistry
Faculty Supervisor: Andrew Ichimura
Anatase films were hydrothermally synthesized on quartz substrate using an aqueous solution of titanium tetrafluoride (TiF4) and nitric acid (HNO3). Anatase crystal grain size, film thickness, and facet shape were evaluated as a function of HNO3 pH and TiF4 concentration. Atomic force microscopy and X ray diffraction were used to image crystal growth and confirm crystallinity, respectively, and Gwyddion was used to evaluate the surface topography. Atomic force microscopy images show square crystal facets that are promising for photocatalysis . Further image processing provides statistical analysis of grain size, film thickness, and orientation. Films were tested for their photocatalytic effectiveness and the production of reactive oxygen species such as hydroxyl radical were quantitatively compared as a function of synthesis conditions. The outcomes of this study guide anatase film synthesis for photocatalysis applications with materials that are abundant, nontoxic, and inexpensive for water remediation.