One-step synthesis of Pt-Nd co-doped Ti/SnO₂-Sb nanosphere electrodes used to degrade nitrobenzene

Ti/SnO₂-Sb electrodes possess high catalytic activity and efficiently degrade nitrobenzene (NB); however, their low service life limits their wide application. In this study, we used one-step hydrothermal synthesis to successfully prepare Pt-Nd co-doped Ti/SnO₂-Sb nanosphere electrodes. Scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were applied to characterize the surface morphology, microstructure, and chemical composition of the electrodes, respectively. The electrochemical activity and stability of the electrodes were characterized via linear sweep and cyclic voltammetry, electrochemical impedance spectroscopy, and an accelerated service life test; their performance for NB degradation was also studied. An appropriate amount of Pt-Nd co-doping refined the average grain size of SnO₂ and formed a uniform and compact coating on the electrode surface. The oxygen evolution potential, total voltammetric charge, and electron transfer resistance of the Ti/SnO₂-Sb-Nd-Pt electrodes were 1.88 V, 3.77 mC/cm², and 11.50 Ω, respectively. Hydroxy radical was the main active radical species during the electrolytic degradation of nitrobenzene with Ti/SnO₂-Sb-Nd-Pt. After Pt-Nd co-doping, the accelerated service life of the electrodes was extended from 8.0 min to 78.2 h (500 mA/cm²); although the NB degradation rate decreased from 94.1 to 80.6%, the total amount of theoretical catalytic degradation of NB in the effective working time increased from 17.4 to 8754.1 mg/cm². These findings reveal good application potential for the electrodes and provide a reference for developing efficient and stable electrode materials.