In-situ preparation of Ti3C2/Ti3+-TiO2 composites with mosaic structures for the adsorption and Photo-degradation of flowing acetaldehyde under visible light

Photocatalytic degradation has been proven to be an effective way in the elimination of gaseous acetaldehyde. This work provided a facile in-situ method for the fabrication of Ti3C2/Ti3+-TiO2 photocatalysts by oxidizing Ti3C2 with H2O(2). A novel mosaic structure formed by small Ti3+-TiO2 nanoparticles embedded in Ti3C2 layers was obtained by adjusting the synthesis parameters. Compared with pure Ti3C2, a 60-fold increase in the BET-SSA was observed in Ti3C2/Ti3+-TiO2 composites, which benefits the capture of the flowing acetaldehyde gas. Self-doped TiO2 nanoparticles induced by the incomplete oxidation process enabled the photodegradation of acetaldehyde under visible light. Besides, the closely contact between the two components helps the transfer of photon-induced charge carriers from TiO2 to Ti3C2, which suppressed the recombination of electron-hole pairs and promoted the generation of active radicals. Compared with commercial P25, which has almost no catalytic activity under the irradiation of visible light, a degradation efficiency of around 27% was achieved by applying Ti3C2/Ti3+-TiO2 as the photocatalyst. This work provided a new facile method for the in-situ fabrication of heterogeneous structures for the photocatalytic elimination of acetaldehyde under visible light.