Constructing 3D sandwich-like structured Ti foam/TiO2−x/SnO2-Sb composite electrodes for the degradation of PPCPs.

[Display omitted] • Design of nanoflower rod-like SnO 2 -Sb supported on TiO 2−x for PPCPs degradation. • A Ti3+/O vs -related TiO 2−x was fabricated. • The effects of O vs on conductivity and the ·OH formation were studied via DFT. • Providing new insights into the electrochemical degradation mechanism for AMX. The fabrication of Sb-doped SnO 2 electrode with high catalytic activity and excellent durability for decomposition PPCPs (Pharmaceuticals and personal care products, PPCPs) is challenging. Herein, a Ti3+/O vs -related TiO 2−x is prepared by short-time annealing at low temperature in mixed gas with Zr as a cocatalyst. DFT calculations indicate that the introduction of Ti3+/O vs defects could promote the formation of more ·OH. Then, the nanoflower rod-like SnO 2 -Sb catalytic layer supported on dual-defects TiO 2−x is successfully synthesized by one-step pulse electrodeposition (PLED) combined with hydrothermal methods (H). This newly pulse electrodeposition technique solves the short lifetime problem of SnO 2 -Sb nanoflower electrodes current hydrothermal-based methods. 1O 2 and ·OH are found to be the primary reactive oxygen species (ROSs) by radical quenching tests and electron paramagnetic resonance analysis. The optimized Ti foam/TiO 2−x /SnO 2 -Sb electrode could degrade over 96.3 % of 20 mg L−1 amoxicillin (AMX) within 30 min, corresponding kinetic constant 0.10228 min−1. This will provide inspiration for the construction of defect engineering and new insights for the development of low-cost and high electrooxidation activity Sb-doped SnO 2 electrode. [ABSTRACT FROM AUTHOR]