VLA photocatalysts: Visible Light Active Photocatalyst Materials for Solar Water Purification
The increase of harmful algal blooms by cyanobacteria (Cyano-HABs) in estuaries and freshwater aquatic systems around the world is a major global problem. Cyano-HABs produce and release a variety of cyanobacterial toxins (cyanotoxins) (i.e., hepatotoxins, dermatotoxins, neurotoxins) with extremely high toxicity. The presence of high concentrations of harmful cyanotoxins in aquatic systems that serve or could potentially serve as sources of drinking water supply is a serious threat to human and environmental health. Conventional water treatment technologies are not wholly effective for the removal of these highly toxic naturally occurring toxic organic compounds and there is a critical need to develop new technologies which can effectively remove cyanotoxins from water. This project will be aligned with our project funded under the US-Ireland R&D initiative, which aims to develop a solar driven advanced oxidation technology (AOT) as a viable solution to the problem of cyanotoxin contamination in water. Photocatalysis is an AOT which utilizes lightactivated semiconductors to drive redox processes in water, leading to the destruction of organic pollutants and the inactivation of microorganisms. Titanium dioxide (TiO2) is the most suitable photocatalyst for water treatment; however, it requires UV excitation meaning that only 4% of the solar spectrum can be utilized. The development of visible light active (VLA) photocatalyst materials would be a major step forward towards the effective utilization of solar energy for the treatment of polluted water. Non-metal doped visible light activated (VLA) TiO2 materials are especially promising because they are strong visible-light absorbers and readily sensitize the formation of reactive oxygen species (ROS), which are known to degrade toxic organic pollutants. At present, the chemistry of organic substrates in the presence of irradiated VLA TiO2 is not well understood. This gap in the knowledge base is a critical problem, because it prevents the optimization of these systems for water treatment applications.
Objectives:
(1) Synthesize, characterize and optimize new VLA TiO2 photocatalysts that will be evaluated for the destruction of cyanotoxins in water, (2) Investigate the photoelectrochemical response of VLA TiO2 photocatalysts,
This project will offer the opportunity for the student to spend time working with our project partners in the USA and Dublin.
Personnel Involved
First Supervisor: Byrne, J Dr
Second Supervisor: McLaughlin, JAD Prof
Collaboration: This project does not involve collaboration with another establishment
Synopsis:
The increase of harmful algal blooms by cyanobacteria (Cyano-HABs) in estuaries and freshwater aquatic systems around the world is a major global problem. Cyano-HABs produce and release a variety of cyanobacterial toxins (cyanotoxins) (i.e., hepatotoxins, dermatotoxins, neurotoxins) with extremely high toxicity. Photocatalysis utilizes lightactivated semiconductors to drive redox processes in water, leading to the destruction of organic pollutants and the inactivation of microorganisms. The development of visible light active (VLA) photocatalyst materials would be a major step forward towards the effective utilization of solar energy for the treatment of polluted water.