Impact of Water Treatment Reactor using TiO₂-coated Micropillar Made by UV-NIL

Abstract

Increasing the catalyst surface area is effective for enhancing the photocatalysis effect. To understand the impact of increasing the surface area, micropillar patterns were fabricated using ultraviolet (UV) nanoimprint lithography (UV-NIL). A titanium oxide (TiO₂) layer was coated in a micropillar pattern by dip coating and this was used in a water treatment reactor. Photocatalytic decontamination was investigated using methylene blue (MB) aqueous solution. Changes in concentration of MB were observed during UV exposure to TiO₂ in the MB aqueous solution. As a result, the reaction rate of the 50 μm diameter pillar pattern was accelerated; therefore, increasing the surface area is effective for photocatalysis using TiO₂. On the other hand, the reaction rate of an 18.8 μm diameter pillar pattern was smaller than that of a flat surface because of a certain level of water-shedding effect.