Solar light induced rhodamine B degradation assisted by TiO2–Zn–Al LDH based photocatalysts

Abstract

© 2014 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved. A series of TiO2/Zn-Al layered double hydroxides (LDHs) based composites were synthesized and their photocatalytic efficiency in rhodamine B photodegradation reaction under solar light irradiation was tested. The aim of this study was to develop photocatalysts based on TiO2/Zn-Al layered double hydroxides that can be activated by solar light irradiation. The influence of TiO2 doping (1, 2 and 3 mass%) on the photocatalytic properties of developed TiO2/Zn-Al LDHs nanocomposites was studied. Different photocatalytic behaviour of composites was interpreted in correlation to their structural, textural, morphological properties and kinetic parameters. All nanocomposites were active in the selected reaction. It was observed that the presence of Zn2TiO4 coupled with the ZnO phase contributes to the activity provoked by solar light irradiation. The photodegradation follows the pseudo first-order kinetics in accordance with the Langmuir-Hinshelwood model. The kinetic study suggested that the applied synthesis methodology resulted in homogeneous distribution of TiO2 and other active components on the photocatalyst surface leading to better accessibility of active sites. The developed synthesis method enables favourable interactions among active phases. Novel TiO2/LDH based photocatalysts are advantageous considering the low-cost and simple preparation, ensuring high photodegradation efficiency, making them appealing for the application in the field of water treatment.