Synergistic mineralization of the herbicide diuron via combined electro-photocatalysis and electro-Fenton processes using a bifunctional BDD//TiO ₂ anode

Abstract This work investigates the combined application of anodic oxidation, electro-Fenton, and heterogeneous photocatalysis for the efficient removal of diuron in a small-scale electrochemical system. The reactor was equipped with a carbon felt cathode and a bifunctional BDD//TiO 2 anode, which allows the concurrent generation of hydroxyl radicals via electrochemical and photocatalytic pathways. The structural and morphological properties of the modified anode were examined using scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), and X-ray diffraction analyses (XRD), confirming the successful deposition of TiO 2 onto the BDD surface. Under optimized operating conditions (Fe 2+ concentration of 0.2 mM, current of 600 mA, and pH 3), the process achieved up to 93 % mineralization of diuron after 2 h of electrolysis, demonstrating a clear synergistic effect and enhanced overall treatment performance.