Synthesis of magnetically removable photocatalyst based on bismuth doped YFeO₃

We report the photocatalytic activity of Y_1-xBi_xFeO₃ (0.1 ≤ x ≤ 0.5) powders under visible light irradiation, synthesized by assisted high-energy ball milling. X-ray diffraction (XRD) and Rietveld refinement, confirm the synthesis of pure bismuth doped yttrium orthoferrite for doped levels up to 30% mol. At higher doping levels, the orthoferrite phase transforms partially to garnet structure. The substitution of yttrium by bismuth changes the magnetic order, from antiferromagnetic to ferromagnetic, evaluated by means of vibrating sample magnetometry (VSM), this behavior can be useful for its recovery. Band gap values around ~2 eV, obtained from UV–visible diffuse reflectance spectroscopy (DRS), show that the synthesized compounds absorb visible light. The synthesized materials show high photocatalytic degradation of methylene blue under visible light irradiation, regardless of bismuth content. Photo-Fenton experiments demonstrated an improvement in the photodegradation. The bismuth doped YFeO₃ appears as a novel magnetically recoverable photocatalyst for water remediation.