Unveiling the photocatalytic potential of Co-doped BaBiO3 through facile sol-gel synthesis and comprehensive characterization

In this study, powders of BaBi (1- x ) Co x O 3 (with x = 0, 1, 2, 4, and 8 mol%) were synthesized using a sol-gel method. These samples were characterized by several techniques, including X-ray diffraction (XRD), Raman scattering, UV–Visible spectroscopy, X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS, Mott-Schottky), and field-emission scanning electron microscopy (FESEM) with associated EDX chemical analysis. The photocatalytic properties were then assessed against methylene blue (MB) dye. The results indicate that Co doping preferentially occurs at the Bi 3+ sites, leading to the formation of defects in the BaBiO 3 lattice. These defects significantly enhance the photocatalytic activity, leading to approximately 80% MB degradation within 120 min. The photocatalytic activity of BBO against MB dye showed a 14% increase in efficiency under acidic pH conditions, whereas the BBO8C sample proved to be 22% more efficient in a neutral medium compared to the acidic environment. The photocatalytic process was primarily driven by electron-mediated phenomena, as indicated by the 8% and 71% reductions in activity for BBO and BBO8C, respectively, upon the addition of electron scavengers. The findings suggest that Co-doped BaBiO 3 is a promising material for liquid waste treatment, demonstrating effectiveness in degrading methylene blue dye under various environmental conditions. • Facile sol-gel synthesis of Co-doped BaBiO 3 without secondary phases. • Co doping shifts the CB from −0.26 to −0.77 V for enhanced photoactivity. • BaBiO 3 :8%Co achieved 80% degradation of MB dye within 120 min. • The photocatalytic process is primarily driven by electrons. • High chemical stability and reusability over four consecutive catalytic cycles.