Revealing the ZrO2 crystal effect of Pd/ZrO2 catalyst for toluene combustion: A combined DRIFTS and DFT study

Boosting Photothermocatalytic Oxidation of Toluene Over Pt/N-TiO2: The Gear Effect of Light and Heat

“…There were several absorption bands in the in situ DRIFTS spectra of Pt/N-TiO 2 -H 2 . The bands near 1622, 1595, and 1583 cm –1 correspond to the formation of CO group in the aldehyde species, , and the peaks located at 1524 and 1451 cm –1 are identified as the symmetric and asymmetric O–CO vibrational modes of benzoate species . The intensity of the vibration bands due to aldehyde species (at 1622 cm –1 ) decreases with the temperature rise, while the intensity of bands related to carboxylate species (at 1524 and 1451 cm –1 ) increases.…”

“…Furthermore, we examined the intermediate products of the subsequent photocatalytic oxidation following thermocatalytic toluene oxidation (Figure S21). Peaks assigned to anhydride species (1734 and 1717 cm –1 ) and aldehyde species (at 1647, 1595, and 1583 cm –1 ) became apparent, , and the bands related to carboxylate species (at 1559, 1540, 1451, and 1415 cm –1 ) were observed to be enhanced under light irradiation at room temperature. − Moreover, additional peaks assigned to the methyl (−CH 3 ) group (3073, 2952, and 2874 cm –1 ) on small-molecular species appeared under light irradiation, indicating the deep oxidation of toluene.…”

“…The bands near 1622, 1595, and 1583 cm −1 correspond to the formation of C�O group in the aldehyde species, 44,45 and the peaks located at 1524 and 1451 cm −1 are identified as the symmetric and asymmetric O−C�O vibrational modes of benzoate species. 46 The intensity of the vibration bands due to aldehyde species (at 1622 cm −1 ) decreases with the temperature rise, while the intensity of bands related to carboxylate species (at 1524 and 1451 cm −1 ) increases. A new peak of carboxylate at 1430 cm −1 is most evidently formed on Pt/N-TiO 2 -H 2 with the rise in temperature.…”

Catalytic Oxidation of Toluene over Pt/CeO2 Catalysts: A Double-Edged Sword Effect of Strong Metal–Support Interaction

“…The wake band (at 1106 cm −1 ) and the small shoulder band (at 1640 cm −1 ) are ascribed to the v(C−O) stretching vibrations of alkoxide species and v(C�O) stretching vibrations of aldehydic species, respectively, which are identified to benzyl alcohol and benzaldehyde due to the partial oxidation of toluene. 51,52 For Pt/CeO 2 -0.25 and Pt/CeO 2 -0.5 catalysts, the shoulder band (at 1640 cm −1 ) becomes stronger, indicating that more oxide intermediates would be produced and accumulated on these catalysts compared with Pt/CeO 2 . Especially for the Pt/CeO 2 -1 catalyst, deeper oxidation products of carboxylates (bands at 1517 and 1546 cm −1 ) are found, suggesting that the toluene oxidation process proceeds further on the richer-electron Pt sites.…”

Crystalline modulation of zirconia for efficient nitrate reduction to ammonia under ambient conditions

“…26 Luo et al reported that t-ZrO 2 contributed to the formation of highly reactive PdO species that further promoted the toluene oxidation. 27 Zhou et al revealed that ZrO 2 with mixed-phases of monoclinic and tetragonal exhibited the highest activity and stability toward methyl laurate hydrogenation. 28 Hu et al reported that m-ZrO 2 as a catalyst carrier was more active than t-ZrO 2 during N 2 O decomposition.…”