Photothermal Synergistic Effect of Pt₁/CuO-CeO₂ Single-Atom Catalysts Significantly Improving Toluene Removal

Abstract

Photothermal synergistic catalytic oxidation of toluene over single-atom Pt catalysts was investigated. Compared with the conventional thermocatalytic oxidation in the dark, toluene conversion and CO 2 yield over 0.39Pt 1 /CuO-CeO 2 under simulated solar irradiation (λ = 320−2500 nm, optical power density = 200 mW cm −2 ) at 180 °C could be increased about 48%. An amount of CuO was added to CeO 2 to disperse single-atom Pt with a maximal Pt loading of 0.83 wt %. The synergistic effect between photo-and thermocatalysis is very important for the development of new pollutant treatment technology with high efficiency and low energy consumption. Both light and heat played an important role in the present photothermal synergistic catalytic oxidation. 0.39Pt 1 /CuO-CeO 2 showed good redox performance and excellent optical properties and utilized the full-spectrum solar energy. Light illumination induced the generation of reactive oxygen species ( • OH and • O 2 − ), which accelerated the transformation of intermediates, promoted the release of active sites on the catalyst surface, and improved the oxidation reaction.

Enhanced Water Resistance and Catalytic Performance of Ru/TiO2 by Regulating Brønsted Acid and Oxygen Vacancy for the Oxidative Removal of 1,2-Dichloroethane and Toluene

“…All of these results indicate that Ru/TiO x possesses a strong ability to break the benzene ring and excellent redox ability. As revealed by the adsorption of reactant molecules (Figure D), the characteristic bands at 1523 and 1615 cm –1 were related to the adsorption of toluene at the oxygen vacancies in Ru/TiO x , while the one at 1523 cm –1 corresponded to the asymmetric stretching vibration of the benzoate species, indicating the formation of the aromatic cyclic carboxylic acid. − The characteristic bands at 1238 and 1284 cm –1 were due to the vibration signals of 1,2-DCE adsorbed at the oxygen vacancies and the alcohol species on the catalyst surface, respectively, which was quite different from that on the Ru/TiO 2 catalyst. This result proves that the Ru/TiO x catalyst exhibits weak competitive adsorption of 1,2-DCE and toluene, and the creation of oxygen vacancies provides sufficient adsorption and oxidation sites.…”

Synergistic Effect of Reactive Oxygen Species in Photothermocatalytic Removal of VOCs from Cooking Oil Fumes over Pt/CeO2/TiO2

“…The O ads /O latt values on the Pt/CeO 2 /TiO 2 and Pt/TiO 2 samples were 0.14 and 0.09, respectively, which were consistent with their photothermocatalytic activity changing trend. A higher oxygen vacancy (OV) density was more beneficial for the activation of O 2 molecules, thus forming the electrophilic O ads species. , …”

“…The largest oxygen desorption area of the Pt/CeO 2 /TiO 2 sample indicates that the loading of CeO 2 and Pt nanoparticles can improve the oxygen adsorption capacity of the sample, which was favorable for the deep oxidation of VOCs. 8 The XPS technique was used to further determine the oxygen species on the surface of Pt/CeO 2 /TiO 2 and Pt/TiO 2 . The O 1s XPS spectrum of the Pt/CeO 2 /TiO 2 or Pt/TiO 2 sample (Figure 3C) was decomposed into three components, including the O latt species at binding energy (BE) = 529.8 eV, the O ads species at BE = 531.2 eV, and the surface hydroxyl group species in a small amount of adsorbed water or the surface carbonate species at BE = 532.3 eV.…”

Recent progresses on single-atom catalysts for the removal of air pollutants

“…It was ascribed to the high surface temperature stemming from excellent light-thermal conversion ability and the enhanced low-temperature reducibility by Pt single-atoms. Besides, the synergistic effect between photocatalysis and thermocatalysis over Pt 1 /CuO-CeO 2 can achieve higher activity than individual thermocatalysis, with toluene conversion elevated by about 48% at 180°C ( Feng et al, 2022b ). Reactive oxygen species (∙OH and∙O 2 − ) of photocatalysis further promote rapid transformation of the intermediates, accelerating release of the active sites.…”