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Stable and efficient SnO2 electrodes are very promising for effectively degrading refractory organic pollutants in wastewater treatment. In this regard, we firstly prepared Ti3+ self‐doped urchin‐like rutile TiO2 nanoclusters (TiO2‐xNCs) on a Ti mesh substrate by hydrothermal and electroreduction to serve as an interlayer for the deposition of Sb−SnO2. The TiO2‐xNCs/Sb−SnO2 anode exhibited a high oxygen evolution potential (2.63 V vs. SCE) and strong ⋅OH generation ability for the enhanced amount of absorbed oxygen species. Thus, the degradation results demonstrated its good rhodamine B (RhB), methylene blue (MB), alizarin yellow R (AYR), and methyl orange (MO) removal performance, with the rate constant increased 5.0, 1.9, 1.9, and 4.7 times, respectively, compared to the control Sb−SnO2 electrode. RhB and AYR degradation mechanisms are also proposed based on the results of high‐performance liquid chromatography coupled with mass spectrometry and quenching experiments. More importantly, this unique rutile interlayer prolonged the anode lifetime sixfold, given its good lattice match with SnO2 and the three‐dimensional concave–convex structure. Consequently, this work paves a new way for designing the crystal form and structure of the interlayers to obtain efficient and stable SnO2 electrodes for addressing dye wastewater problems. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ti 3 C 2 served as a pore-forming agent for preparing porous Sb-SnO 2 electrode. • Ti 3 C 2 -contained electrolyte could regulate the Sb-Sn alloy nucleation process to decrease its domain size. • High-conductive Ti 3 C 2 improves the metal ions diffusion process to increase the Sb-SnO 2 loading amount. • Ti 3 C 2 -modified Sb-SnO 2 electrode achieved good degradation performance for methylene blue, methylene orange, norfloxacin, and P-phenylenediamine. Sb-SnO 2 is an appealing electrode for degrading organic pollutants in wastewater treatment, albeit further modifications are needed for its inefficient electrochemical oxidation capacity. In this work, we prepared Ti 3 C 2 -modified Sb-SnO 2 electrode by electrodeposition technology. High-conductive MXene matrix regulated the Sb-Sn alloy nucleation process to decrease its domain size during deposition and generated pores during the annealing process. When introducing 20 mg MXene into the electrolyte, the obtained Sb-SnO 2 electrode (Ti 3 C 2 -20) presented a larger oxygen evolution over-potential (2.32 V vs SCE), increased amount of active sites, and enlarged electrochemical specific surface area (∼4.4-fold) than the unmodified electrode, resulting in a promoted OH generation ability (∼7.4 times). Methylene blue (MB), methyl orange (MO), norfloxacin (NOR), and P-phenylenediamine (PPD) were effectively degraded by the Ti 3 C 2 -20 anode with economic energy consumption. Moreover, the Ti 3 C 2 -20 electrode also featured a longer lifetime, almost fivefold, than the unmodified Sb-SnO 2 electrode due to its larger loading amount and decreased charge transfer resistance. Consequently, this work offers a new perspective for designing efficient and stable porous electrodes to address water pollution issues. [ABSTRACT FROM AUTHOR]

• A novel Ce and Sb co-doped SnO 2 nanoflowers electrode was prepared by a two-step (hydrothermal and thermal decomposition) method. • The Ti/Ce-Sb-SnO 2 NFs electrode achieved nearly 100% methylene blue removal efficiency within 90 min. • The electrochemical stability of the anode was prolonged from 8.2 h to 15.5 h after the introduction of Ce. Nanostructured Sb-SnO 2 electrodes with high electrochemical activity and stability are urgently desired for electrochemical oxidation of refractory organics in wastewater treatment, yet hard to be controlled and synthesized. Hence, we combined the hydrothermal method and thermal decomposition technologies to prepare a novel Ce and Sb co-doped SnO 2 nanoflowers electrode (Ti/Ce-Sb-SnO 2 NFs). The incorporation of Ce endowed the Ti/Ce-Sb-SnO 2 NFs anode with an increased oxygen evolution over-potential (OEP) (1.99 V vs. SCE), lower charge transfer resistance (7.54 Ω⋅cm2), large specific electrochemical active surface area (141.83), a great number of active sites and superior •OH generation ability. Consequently, nearly 100% decolorization efficiency and 91.45% chemical oxygen demand (COD) mineralization efficiency of methylene blue (MB) (20 mg/L) were achieved by the Ti/Ce-Sb-SnO 2 NFs anode within 90 min. Additionally, the Ti/Ce-Sb-SnO 2 NFs anode stability was also improved with a longer accelerated lifetime (15.5 h) than the given Ti/Sb-SnO 2 NFs electrode (8.2 h). We also prepared other nanostructured (nanoparticles, nanoclusters and nanosheets) Sb-SnO 2 electrodes with high oxidation capacity utilizing this two-step method, which demonstrated its great versatility. Accordingly, this work could provide a new strategy for fabricating efficient and stable rare earth elements (Ce, Nd, La, etc.) and Sb co-doped SnO 2 nanostructured electrodes for decomposition organic pollutants in the field of wastewater treatment. [Display omitted] [ABSTRACT FROM AUTHOR]