(291f) Optimization of Titanium Dioxide Nanotubes for Bacterial Inactivation

Water quality is a growing concern around the globe and the development of renewable, less harmful sources of water purification is a field of increasing interest. Advanced oxidative processes (AOP) such as chlorination are used to provide clean water worldwide. However, many large scale AOPs currently in use are energy intensive or form unhealthy for human byproducts. Titanium dioxide (TiO₂) is a solid state photocatalyst that unlike chlorine and other catalysts used in advanced oxidation processes, is a non-consumable source whose oxidative species can be produced directly from the sun. Nanotube arrays provide an immobilized, well-ordered structure which yields higher surface area and promotes higher photocatalytic activity than other nanostructures. Little to no research has been done on the possibility of large-scale application of Titanium Dioxide Nanotube Arrays (TNAs) for the formation of biocidal reactive oxidative species (ROS) although previous studies have shown that UV activated microfluidic TNA channels have biocidal capabilities and do not form unhealthy to human byproducts. Initial testing using E. coli shows that electrochemically polishing as a pretreatment to anodization plays a key role in the optimization of TNAs so that biocidal activity can be achieved with macrofluidic flow rates.