Green combustion synthesis of monoclinic Bi₂₆Mo₁₀O₆₉ nanoparticles using simarouba glauca leaves for efficient visible-light-driven photocatalytic degradation of Rose Bengal dye

The development of visible-light-active photocatalysts through sustainable synthesis routes is crucial for advancing environmental remediation technologies. Therefore, Well-designed photocatalysts with high catalytic activity attracted a lot of interest due to their remarkable charge separation capabilities and efficient absorption of visible light. In this work, bismuth molybdate (Bi₂₆Mo₁₀O₆₉) nanoparticles were synthesized via a green combustion process employing powdered Simarouba glauca leaves as an eco-friendly fuel. XRD pattern confirmed the formation of a monoclinic Bi₂₆Mo₁₀O₆₉ phase with space group P2/c (13), evidencing high crystallinity and phase purity. Complementary characterization techniques, including FT-IR, UV-DRS, SEM-EDAX, TEM, and PL, were utilized to elucidate the structural, morphological, and optical features of the material. The nanoparticles exhibited a direct band gap of 2.22 eV, indicative of efficient visible-light absorption. Photocatalytic evaluations indicated remarkable degradation efficiency toward Rose Bengal dye (99.1%) under visible-light irradiation at pH 5, can be related to efficient charge separation and the formation of reactive oxygen species (ROS). Scavenger and fluorescent probe tests indicated that hydroxyl radicals (•OH) played a significant role in the breakdown mechanism. Furthermore, recyclability tests demonstrated minimal loss in activity over successive cycles, affirming the catalyst’s stability and reusability. These findings establish green-synthesized Bi₂₆Mo₁₀O₆₉ nanoparticles as an efficient, stable, and environmentally benign photocatalyst, offering a promising route for the sustainable degradation of dye-laden wastewater.