Research Information System
Reaction Kinetics, Mechanisms and Catalysis, 2024 (SCI-Expanded)
Monoclinic BiVO4 was synthesized by a modified sol–gel technique, using bismuth nitrate pentahydrate Bi(NO3)3·5H2O and vanadium pentoxide V2O5 as precursors, dissolved in nitric acid and hydrochloric acid. The prepared samples were characterized by Scanning Electron Microscopy with Energy Dispersive X-ray Analysis (SEM–EDX), Transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), and UV–Vis Diffuse Reflectance Spectroscopy (DRS). The band gap of BiVO4 was determined to be 2.53 eV. The Mott-Schottky plot identifies BiVO4 as a n-type semiconductor with a flat band potential of 0.64 V/SCE and an electron donor density (Nd) of 1.46 × 1016 (site cm−3). Electrochemical impedance spectroscopy confirmed efficient photogenerated electron–hole (e−/h+) pair separation. Under solar irradiation, BiVO4 exhibited high photocatalytic efficiency with 96% methylene blue (MB) degradation achieved within 120 min. The photodegradation process is well fitted by a first-order kinetic model, and parameters affecting MB degradation, such as pH and initial concentration, were optimized. A photocatalytic mechanism was proposed in accordance with the scavenger test.