Fabrication of a novel Ti3C2-modified Sb-SnO2 porous electrode for electrochemical oxidation of organic pollutants

Abstract

Sb-SnO2 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 Ti3C2-modified Sb-SnO2 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-SnO2 electrode (Ti3C2-20) presented a larger oxygen evolution over-potential (2.32 V vsSCE), 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 Ti3C2-20 anode with economic energy consumption. Moreover, the Ti3C2-20 electrode also featured a longer lifetime, almost fivefold, than the unmodified Sb-SnO2 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.