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 near zero.

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