Impact of Fluoride on Anatase Titanium Dioxide Thin Films for Energy Applications
Brandon Le
Department of Chemistry & Biochemistry
Faculty Supervisor: Andrew Ichimura
This project explores how fluoride affects the crystal growth of anatase titanium dioxide (TiO₂). When activated by ultraviolet light, TiO₂ has numerous energy and environmental applications, such as water splitting and remediation. Understanding the factors that influence its crystal growth can therefore advance photoelectrocatalytic (PEC) technologies.
TiO₂ thin films are hydrothermally synthesized, a method that enables precise control of solution parameters. In this study, we vary the fluoride-to-titanium ion ratio to examine changes in film morphology and PEC performance. The films’ structure and surface features are characterized using X-ray diffraction, scanning electron microscopy, and atomic force microscopy. PEC activity is evaluated through cyclic voltammetry, measuring the current density of each film. By correlating morphological changes with PEC performance, we aim to identify the optimal fluoride ratio to enhance TiO₂ based energy and environmental applications.
Preliminary results show that a 4.5:1 fluoride to titanium ratio enables the most optimal PEC performance (current density of 2.1 mA/cm^2) due to its {001} oriented grains and relatively smooth surface roughness shown with AFM. Further increasing or decreasing the fluoride:titanium ratio inhibits PEC performance which still is to be discovered.