Preparation of RuO2-TiO2/Nano-graphite composite anode for electrochemical degradation of ceftriaxone sodium.

Graphite-like material is widely used for preparing various electrodes for wastewater treatment. To enhance the electrochemical degradation efficiency of Nano-graphite (Nano-G) anode, RuO2-TiO2/Nano-G composite anode was prepared through the sol-gel method and hot-press technology. RuO2-TiO2/Nano-G composite was characterized by X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy and N2 adsorption-desorption. Results showed that RuO2, TiO2 and Nano-G were composited successfully, and RuO2 and TiO2 nanoparticles were distributed uniformly on the surface of Nano-G sheet. Specific surface area of RuO2-TiO2/Nano-G composite was higher than that of TiO2/Nano-G composite and Nano-G. Electrochemical performances of RuO2-TiO2/Nano-G anode were investigated by cyclic voltammetry, electrochemical impedance spectroscopy. RuO2-TiO2/Nano-G anode was applied to electrochemical degradation of ceftriaxone. The generation of hydroxyl radical (OH) was measured. Results demonstrated that RuO2-TiO2/Nano-G anode displayed enhanced electrochemical degradation efficiency towards ceftriaxone and yield of OH, which is derived from the synergetic effect between RuO2, TiO2 and Nano-G, which enhance the specific surface area, improve the electrochemical oxidation activity and lower the charge transfer resistance. Besides, the possible degradation intermediates and pathways of ceftriaxone sodium were identified. This study may provide a viable and promising prospect for RuO2-TiO2/Nano-G anode towards effective electrochemical degradation of antibiotics from wastewater.