Synthesis of the ZnTiO 3 /TiO 2 Nanocomposite Supported in Ecuadorian Clays for the Adsorption and Photocatalytic Removal of Methylene Blue Dye

摘要

Currently, the study of semiconductor materials is very promising for the photocatalytic remediation of hazardous organic substances present in the air and water. Various semiconductors have been investigated in this interesting photo-assisted methodology, among them metal oxides such as ZnO, TiO 2 and their derivatives. In this study, ZnTiO 3 /TiO 2 was synthesized by the sol-gel method using Ti(OC 3 H 7 ) 4 and Zn(CH 3 COO) 2 · 2H 2 O as reagents. The role of several conditions such as synthesis temperature and TiO 2 :ZnO proportion on the morphology and purity of compounds obtained was studied, and the suitable conditions for the synthesis of photocatalysts were determined. Various techniques were used to conduct a systematic investigation on the structural, morphological, and photocatalytic properties of ZnTiO 3 /TiO 2 . Scanning Electron Microscopy (SEM) images show that ZnTiO 3 /TiO 2 have a typical particle size of approximately 100 nm with a quasi-spherical shape. The adsorption and photocatalytic activity were investigated by the decolorization of Methylene Blue (MB) as an organic contaminant under UV irradiation both in TiO 2 and ZnTiO 3 /TiO 2 supported over some Ecuadorian clays. The materials evaluated were prepared in the shape of 0.2 cm (diameter) and 1.0 cm (length) cylindrical extrudates. The degradation percentage of MB obtained was 85% approximately after 150 min of irradiation. The results obtained allow us to conclude that these synthesized materials can be used as adsorbents and photocatalysts.