Crystalline TiO2 supported on stainless steel mesh deposited in a one step process via pulsed DC magnetron sputtering for wastewater treatment applications

TiO2 thin films were deposited on woven stainless-steel mesh by pulsed DC magnetron sputtering, at room temperature without substrate bias or annealing. Woven stainless-steel mesh is inexpensive, flexible, semi-transparent and has a high surface area. This coating/substrate combination was selected for future photocatalytic reactor integration. The effect of operating pressure and magnetron power on coating crystallinity and photocatalytic activity were investigated. Results indicate that magnetron power is a key factor, as it affects the crystallinity and morphology of the thin films. A combination of low pressure and high-power lead to a one-step synthesis of TiO2 coatings with a mixed anatase and rutile phase. An optimised sample was produced and tested for methylene blue, methyl orange and rhodamine B decomposition under UV-A. Using various trapping agents, •OH and O2-• radicals were identified as the main photogenerated species responsible for the model pollutant degradation. Finally, durability tests revealed little to no photocatalytic performance deterioration after ten repeated cycles. This confirmed the suitability of this coating/substrate combination for future photocatalytic reactor integration. https://doi.org/10.1016/j.cviu.2017.00.000