Facile synthesis of TiO2-supported Al2O3 ceramic hollow fiber substrates with extremely high photocatalytic activity and reusability

Abstract

TiO2 oxide was deposited on a microstructured alpha-Al2O3 ceramic hollow fiber substrate by a simple one-step solution-immersion process with tetraethyl orthosilicate (TEOS) as a binder. The effects of the starting coating solution's composition on the photocatalytic properties of TiO2 powders deposited on a substrate was determined by using TiO2-supported Al2O3 ceramic hollow fiber substrates fabricated from coating solutions with different compositions and examining the substrates' effect on the methylene blue (MetB) degradation reaction under ultraviolet light. A strong correlation was observed between the initial coating solution compositions and the final photocatalytic characteristics of the TiO2-supported Al2O3 ceramic hollow fiber substrates. Under optimal conditions, the MetB removal efficiency reached about 91% in a few minutes. To the best of our knowledge, this is the highest and most rapidly attained MetB removal efficiency reported for TiO2-supported Al2O3 ceramic hollow fiber substrates. Furthermore, apart from attaining an extremely high photocatalytic activity within minutes, the fabricated TiO2-supported Al2O3 ceramic hollow fiber substrates exhibited high photocatalytic stability even after several cycles.