Boosting photocatalytic activity of C-F-TiO2 nanosheets derived from in-situ pyrolysis of MXene.

[Display omitted] • C and F co-doped TiO 2 nanosheets were synthesized by pyrolysis of layered MXene. • C-F-TiO 2 was applied to photocatalytic degradation of 2,4,6-TCP. • The doping of C and F increased the generation of active radicals and decreased the band gap. • The recombination rate of photogenerated electron-hole was inhibited. • C-F-TiO 2 nanosheets exhibited remarkable photocatalytic activity. Nonmetal doping is widely used in the modification of titanium dioxides (TiO 2) for photocatalytic applications. As a typical two-dimensional layered nanomaterial, the excellent physical and chemical properties of MXene materials have been the focus of current research. In this study, carbon and fluorine co-doped MXene derived TiO 2 nanosheets (labelled as C-F-TiO 2) were successfully synthesized and used as catalysts for degrading 2,4,6-trichlorophenol (2,4,6-TCP) under UV light irradiation. The C-F-TiO 2 with ultrathin nanosheet structure enhanced light absorption range and decreased the bandgaps. The degradation efficiency of 2,4,6-TCP by C-F-TiO 2 was over 99 % in 90 min, and the degradation rate was more than twice that of commercial TiO 2. The degradation rate still remained about 90 % in 90 min after five cycles. The results of quenching experiments and electron spin resonance (ESR) illustrated that more reactive oxygen species (ROS) were generated in the C-F-TiO 2 /UV system, which was 1.5 times that of commercial pure TiO 2 , and •O 2 – was the dominant ROS for 2,4,6-TCP degradation. This study provided insight to utilize physicochemical characteristics of MXene to synthesize non-metal co-doped TiO 2 nanosheet as a catalyst, exhibiting excellent reactivity in the potential application for organic pollutant degradation. [ABSTRACT FROM AUTHOR]