Strategies for Designing Morphology Control and Oxygen‐Vacancy Fe‐Doped MoO ₃ for Enhanced Photocatalytic Performance

ABSTRACT Dye‐polluted water poses a significant environmental threat due to its detrimental impact on ecosystems, water resources, and human health. In this work, MoO 3 and different concentrations of Fe‐doped MoO 3 were prepared using a hydrothermal process for visible light‐induced Rhodamine B (RhB) degradation. The structural, morphological, and chemical properties were systematically characterized using x‐ray diffraction (XRD), field emission scanning electron microscopy (FESEM), high‐resolution transmission electron microscopy (HRTEM), and x‐ray photoelectron spectroscopy (XPS), respectively. It was found that MoO 3 can be controllably tuned from a nanorod to a nanoflake by adjusting the Fe doping concentration. Furthermore, Fe doping into the MoO 3 lattice introduces an oxygen vacancy, which promotes photocatalytic efficiency. The optimum Fe (6%)‐doped MoO 3 demonstrates outstanding RhB photodegradation performance with the rate constant of 0.04352 min −1 , which is 12.8 times higher than the pristine MoO 3 . The efficient photocatalytic degradation of optimum Fe‐doped MoO 3 is attributed to the sub‐band forming near the conduction band of MoO 3 , which reduces the photogenerated electron and hole. The study acknowledges the inherent scientific challenges in precisely controlling the doping process to achieve uniformity and reproducibility in the material properties.