Synergistic effect between Ce-doped SnO2 and bio-carbon for electrocatalytic degradation of tetracycline: Experiment, CFD, and DFT

Carbon-based sandwich-like electrocatalyst with a hierarchical structure, carbon sheet (CS)-loaded Ce-doped SnO2 nanoparticles, were successfully prepared using a simple method, which presented a high-efficiency electrocatalytic performance for tetracycline decomposition. Among them, Sn0.75Ce0.25Oy/CS exhibits superior catalytic activity, such as more than 95% of tetracycline was removed (120 min), and over 90% of total organic carbon was mineralized (480 min). It is found from morphology observation and computational fluid dynamics simulation that the layered structure is conducive to improving the mass transfer efficiency. Through X-Ray powder diffraction, X-ray photoelectron spectroscopy, Raman spectrum, and density functional theory calculation analyze that the structural defect in Sn0.75Ce0.25Oy caused by Ce doping is considered to play the key role. Moreover, electrochemical measurements and degradation experiments further prove that the outstanding catalytic performance is attributable to the initiated synergistic effect established between CS and Sn0.75Ce0.25Oy. These results explain the effectiveness of Sn0.75Ce0.25Oy/CS for the remediation of tetracycline-contaminated water and mitigating the potential risks and imply that the Sn0.75Ce0.25Oy/CS composite has a deeply practical value in tetracycline wastewater degradation and a promise for further application.