BFO thin film on the stainless steel mesh by anodic EPD: A visible light photocatalyst for degradation of Rhodamin B

• Published in: Journal of photochemistry and photobiology. A, Chemistry. Chemistry., 2018-10, Vol.365, p.185-198
• Main Authors: Zargazi, Mahboobeh, Entezari, Mohammad H.
• Format: Article
• Language: English
• Subjects: Anions; Atomic beam spectroscopy; Atomic force microscopy; Bismuth ferrite; Catalytic activity; Chemical contaminants; Dispersants; Dispersion; Electrochemical impedance spectroscopy; Electrochemistry; Electrophoretic deposition; Energy dispersive X ray spectroscopy; Holes (electron deficiencies); Irradiation; Light irradiation; Magnetic fields; Photocatalysis; Photocatalysts; Photodegradation; Scanning electron microscopy; Separation; Slurries; Spectroscopy; Stainless steel; Stainless steel mesh; Stainless steels; Substrates; Surface roughness; Thin film; Thin films; Visible light photocatalytic activity; X ray spectra; X-ray spectroscopy
• ISSN: 1010-6030; 1873-2666
• DOI: 10.1016/j.jphotochem.2018.07.042

The schematic shows the process of BFO thin film synthesis as a visible light photocatalyst. Furthermore, the photocatalytic activity of thin film was investigated for degradation of RhB in a rotating system. The removal efficiency of RhB was evaluated under different conditions (BFO powder, BFO/glass, BFO/PAS/SS mesh, BFO/SS mesh). BFO/PAS/SS mesh and BFO/SS mesh are films before and after sintering, respectively. BFO/glass is BFO film supported on the nonconductive glass. [Display omitted] •Synthesis of BFO thin films for the first time from nanosized particles by electrophoretic deposition.•Water as a proper medium (nonflammable and nontoxic) was used in electrophoretic deposition.•Stainless steel mesh was used as a substrate with high surface area and high conductivity.•Photocatalytic degradation was the highest for the film in comparison with other cases. Bismuth ferrite thin film as an active visible light photocatalyst was synthesized by anodic electrophoretic deposition on the stainless steel mesh. The stability of suspension was studied in the presence of dispersant under different conditions through the sediment percentage measurements. The effect of various dispersants was also evaluated on the stabilization of BFO aqueous suspension. The films were characterized by scanning electron microscopy (SEM) equipped with energy-dispersive X-ray spectroscopy (EDS), atomic force microscopy (AFM), and magnetic force microscopy (MFM). Electrochemical impedance spectroscopy (EIS) was applied to evaluate the separation of photogenerated electron-hole by measured resistance and capacity of films under visible light irradiation. The visible light photocatalytic activity of thin films was investigated by degradation of Rhodamin B subjected to direct solar irradiation in a designed photocatalytic reactor. The film illustrated a better photocatalytic efficiency than slurry state. High efficiency in immobilized film can be attributed to the conductive substrate (stainless steel mesh) that makes better separation of photogenerated electrons and holes. In addition, the fractal dimension measurement indicated that films with high surface roughness improve the light adsorption capacity and leads to enhance the photocatalytic reaction rate. The photocatalytic activity of films was also investigated in the presence of some common anions in Rhodamin B solution. It can be highlighted that the thin film completely removed the dye from aqueous solution and COD reached to ne