Synthesis of mesoporous TiO2 thin films for environmental remediation
TiO2 photocatalysis is a promising oxidation technique capable of removing an extended variety of contaminants at ppb to low ppm levels in water and air. However, TiO2 in aqueous suspension form is impractical as post-treatment recovery of TiO2 particles is energy intensive and would increase the overall capital and running cost of the process. Attempts have been made to immobilise TiO2 particles as thin films. Unfortunately, the efficiency of the immobilised form TiO2 is low due to low specific surface area. High surface area is essential to achieve efficient destruction of contaminants as the photocatalytic reaction is a surface-catalysed reaction.
The aim of this project is to develop mesoporous TiO2 thin films which exhibit high porosity by using polymers as structure directing agents in the sol-gel method. The highly porous nature of the films would offer more active sites for carrying out catalytic reactions.
Major achievements and highlights
Mesoporous TiO2 thin films have been successfully synthesised. By controlling the synthesis conditions such as polymer concentration and humidity, the pore size as well as the film structure can be controlled. From surface area measurements, the mesoporous films were found to possess significantly higher surface areas than the conventional films.
Future plans and directions
The next stage of the project is to elucidate the photocatalytic and photoelectrocatalytic activity of the mesoporous films in a micro-photoreactor. The success in synthesising highly active mesoporus TiO2 thin films would open up substantial opportunities for numerous applications such as self-cleaning surfaces, chemical sensors and solar cells.
Collaborations
Collaborator |
Organisation |
Prof Huijin Zhao |
Griffith University, Queensland |
