Simultaneously activating molecular oxygen and surface lattice oxygen on Pt/TiO 2 for low-temperature CO oxidation.

Developing high-performance Pt-based catalysts with low Pt loading is crucial but challenging for CO oxidation at temperatures below 100 °C. Herein, we report a Pt-based catalyst with only a 0.15 wt% Pt loading, which consists of Pt-Ti intermetallic single-atom alloy (ISAA) and Pt nanoparticles (NP) co-supported on a defective TiO 2 support, achieving a record high turnover frequency of 11.59 s -1 at 80 °C and complete conversion of CO at 120 °C. This is because the coexistence of Pt-Ti ISAA and Pt NP significantly alleviates the competitive adsorption of CO and O 2 , enhancing the activation of O 2 . Furthermore, Pt single atom sites are stabilized by Pt-Ti ISAA, resulting in distortion of the TiO 2 lattice within Pt-Ti ISAA. This distortion activates the neighboring surface lattice oxygen, allowing for the simultaneous occurrence of the Mars-van Krevelen and Langmuir-Hinshelwood reaction paths at low temperatures.