Oxygen vacancy-rich C/Ti3C2/(001)TiO2 hollow microspheres and the photocatalytic degradation of organic pollutants

C/Ti3C2/(001)TiO2 hollow microspheres were prepared by combining the template method, self-assembly and hydrothermal method. Anatase TiO2 nanosheets with rich oxygen vacancies formed on the microspheres and exposed active (001) facets due to the spherical surface. TC was removed 92.3% by C/Ti3C2/(001)TiO2-HMs within 160 min, 28.4% by TiO2 and 49.5% by (001)TiO2/Ti3C2 under the same condition. The high removal efficiency of C/Ti3C2/(001)TiO2-HMs could be because the oxygen vacancies exposed on the surface of (001)TiO2 afforded more active sites, extended the light absorption range and promoted the generation of electron-hole pairs. The composite C/Ti3C2/(001)TiO2 structure could suppress the recombination of electron-hole pairs and prolong their lifetime. The degradation pathway of TC was discussed. The TC removal efficiency of C/Ti3C2/ (001)TiO2-HMs was confirmed by treating the wastewater from the Slender West Lake. The production principle of oxygen vacancy could be used for preparing MXene composites with excellent catalytic properties and the C/ Ti3C2/(001)TiO2-HMs could be a potential choice for treating wastewater.

Automated summary

C/Ti3C2/(001)TiO2 hollow microspheres were prepared via the combination of the template method, self-assembly, and hydrothermal method. The microspheres exhibited anatase TiO2 nanosheets with oxygen vacancies and exposed active (001) facets on the spherical surface. C/Ti3C2/(001)TiO2-HMs showed higher TC removal efficiency (92.3%) compared to TiO2 (28.4%) and (001)TiO2/Ti3C2 (49.5%) due to the presence of oxygen vacancies, extended light absorption range, and promotion of electron-hole pair generation. The composite structure of C/Ti3C2/(001)TiO2 could suppress electron-hole pair recombination and prolong their lifetime, making it a potential choice for wastewater treatment.