Physical Sciences and Mathematics Commons^™

Passive Sampling For Quality Monitoring Of Irish Marine Waters, Philip White

Doctoral

This study details the steps involved in fabrication, deployment and retrieval of mainly polydimethyl siloxane (PDMS) passive sampling devices deployed in a number of locations in and around Ireland in an attempt to derive dissolved water concentrations of contaminants in-situ. PDMS samplers were initially deployed in the Burrishoole catchment, Co. Mayo in conjunction with the collection of biological tissues and sediment to investigate the source of elevated dioxins in the catchment. Passive samplers were used to generate dissolved water concentrations of persistent organic pollutants (POPs) and also to successfully screen for the presence of dioxins in the water column. The …

A Highly Efficient Tio2-Xcx Nano-Heterojunction Photocatalyst For Visible-Light Induced Antibacterial Applications, Vinodkumar Etacheri, Michael Seery, Stephen Hinder, Georg Michlits, Suresh Pillai

Articles

Visible-light-induced antibacterial activity of carbon-doped anatase-brookite titania nano-heterojunction photocatalysts are reported for the first time. These heterostructures were prepared using a novel low temperature (100 °C) non-hydrothermal low power microwave (300 W) assisted method. Formation of interband C 2p states was found to be responsible for the band gap narrowing of the carbon doped heterojunctions. The most active photocatalyst obtained after 60 minutes of microwave irradiation exhibits a 2-fold higher visible-light induced photocatalytic activity in contrast to the standard commercial photocatalyst Evonik-Degussa P-25. Staphylococcus aureus inactivation rate constant for carbon-doped nano-heterojunctions and the standard photocatalyst was 0.0023 and -0.0081 min …

A Review On The Visible Light Active Titanium Dioxide Photocatalysts For Environmental Applications, Miguel Pelaez, Nicholas Nolan, Suresh Pillai, Michael Seery, Polycarpos Falaras, Athanassios G. Kontos, Patrick S.M. Dunlop, Jeremy W.J. Hamiltone, J. Anthony Byrne, Kevin O’Shea, Mohammad H. Entezari, Dionysios D. Dionysiou

Articles

Development of visible light active (VLA) titania photocatalysts

Fujishima and Honda (1972) demonstrated the potential of titanium dioxide (TiO 2) semiconductor mate-rials to split water into hydrogen and oxygen in a photo-electrochemical cell. Their work triggered the development of semiconductor photocatalysis for a wide range of environmental and energy applica-tions. One of the most significant scientific and commercial advances to date has been the development of visible light active (VLA) TiO2 photocatalytic materials. In this review, a background on TiO2 struc-ture, properties and electronic properties in photocatalysis is presented. The development of different strategies to modify TiO2 for the utilization …

Novel Photoelectrochemical Cell For The Remediation Of Organic Compounds In Water, Patrick Enright

Doctoral

Titanium dioxide (TiO2) suspensions have widely been used as photocatalysts, either alone or in a doped form to degrade organic compounds and kill bacteria. Because of its relatively large band gap, UV light has been the most efficient radiation used to allow this catalysis to occur. TiO2 has also been immobilised on electrodes in order to separate the ‘reduction’ and ‘oxidation’ reactions. Typical systems involve the oxidation of a ‘fuel’ at a TiO2 coated anode and the reduction of oxygen at a separate cathode, where the passage of current can be monitored, and this work utilises such a system. In …

Silver Doped Titanium Dioxide Nanomaterials For Enhanced Visible Light Photocatalysis, Michael Seery, Reena George, Suresh Pillai, Patrick Floris

Articles

This paper presents a systematic study on two different preparation methods for titanium dioxide with silver. The silver can be incorporated by irradiating the reaction mixture during preparation to reduce silver ion to silver metal or by direct calcination of the sol–gel material to decompose silver nitrate to silver. Of the two methods, we found the latter produces a more effective photocatalytic material (6–50% improvement in catalytic efficiency), which is attributed to the fact that the silver is homogeneously dispersed throughout the material. The efficiency of the materials were examined using a Q-Sun solar simulator (visible light) and in Dublin …