TiO2 thermal stress deformation induced to promote photocatalytic CO2 reduction

Semiconductor photocatalytic reduction of CO2 is an effective means to achieve the goal of double carbon. TiO2 has received extensive attention as an excellent photocatalyst, but the adsorption of CO2 on the surface of TiO2 is not stable, which greatly inhibits the yield and selectivity of reduction products. In this work, wollastonite was used to reduce the melting temperature of TiO2 and in turn induce thermal stress deformation on the surface of the TiO2 lattice. Characterization and DFT results certified that the lattice stress deformation caused by the contraction of oxygen vacancy enables TiO2 to obtain better carrier transport efficiency and lower activation energy barrier, and also stabilizes the adsorption state of CO2 on the surface of TiO2 crystal, which effectively improved the reduction yield and selectivity of CO2. The CO yield is increased by 5.1 times, reaching up to 2.09 μmolg-1h−1, and the CO selectivity is as high as 91 %. These findings provide valuable insights for the development of efficient and selective photocatalysts for carbon dioxide transformation and pave the way for novel avenues in this research field.