Abstract
Photothermocatalytic oxidation is an environmentally-friendly, low-temperature, and high-efficient method to remove the air pollutant. Yet, the lack of active, inexpensive, and superior stability catalysts has greatly limited its extensive utilization. In this work, the effect of single-atom Pt loading on TiO2 support has been theoretically and experimentally studied to improve photothermocatalytic performance for the toluene combustion through flame spray pyrolysis (FSP). Pt loading can play two crucial roles into TiO2 optimization: (1) The low-valence Pt cation incorporated into TiO2 lattice is dramatically responsible for the anatase-rutile transformation (ART) and formation of sufficient oxygen vacancies; (2) Introducing the defect energy level and Pt-3d orbitals remarkably promote the charge separation efficiency of single-atom catalysts. Moreover, the existence of single-atom Pt nanoparticles can signally boost the activity of surface adsorbed and lattice oxygen, as well as substantially reduce the oxygen vacancy formation energy. Thus, the toluene removal under light irradiation reaches 90% conversion below 160 °C and is maximally 18 °C lower than that under only thermocatalytic oxidation. It is attributed to larger specific surface area (SSA), outstanding low-temperature reducibility, extremely dispersed hybrid PtOx, more surface active oxygen, and higher mobility of bulk oxygen. Interestingly, when the oxygen-fuel equivalent ratio φ distinctly increases by shifting precursor solvent from xylene to ethanol, the photothermocatalytic property of toluene can be remarkably enhanced on single-atom Pt catalysts. It is due to the higher Pt dispersion resulting from more intense burning and drastic turbulent mixing, as well as the superior ratio of the metallic Pt active sites originating from higher flame temperature. Eventually, the rate-determining step of C7H8 combustion on Pt/TiO2 and Cu/TiO2 slab are all the CC bond fracture of maleic anhydride to form acetic anhydride species, with the energy barriers of 112.03 and 188.74 kJ/mol, respectively.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
