PHOTOCATALYTIC PROPERTIES OF BiFeO3 AND Bi5Ti3FeO15 BASED POWDERS

Abstract

Bismuth ferrite (BiFeO3) and bismuth titanate ferrite (Bi5Ti3FeO15) are studied a lot in recent years because of their specific structure and potential to act as single phase multiferrioics. Thanks to the optical band gap energy of 2.3-2.8 eV for BiFeO3 and 1.8- 2.3 eV for Bi5Ti3FeO15, these materials are also interesting for photocatalytic and solar energy applications, and studies of using Bi5Ti3FeO15 for this purpose are very rare. Solgel methods were used to produce BiFeO3 and BiFeO3-modified diatomaceous earth, while Bi5Ti3FeO15 was obtained sol-gel and solid-state methods. These powders were characterized, and their visible light photocatalytic activity for decomposition of methylene blue was tested in acidic, close-to-neutral and alkaline conditions. Fenton-like catalysis was also tested. Influence of synthesis method, microstructure, and catalyst composition on dye degradation will help in proposing the mechanism of adsorption and photocatalytic processes.