Promoting intermediates transformation by boosting H2O dissociation over core-shell Pd@CoO Janus for acetone efficacious oxidation

• Published in: Applied catalysis. B, Environmental Vol. 354; p. 124113
• Main Authors: Wu, Yani, Wang, Yadi, Liu, Jicheng, Jiang, Zeyu, Wan, Jialei, Wang, Jingjing, Chai, Shouning, Ai, Chunli, Dang, Fan, Albilali, Reem, He, Chi
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05.10.2024
• Subjects: Acetone; Aldehyde intermediate transformation; Catalytic oxidation; Core-shell Pd@CoO Janus; H2O dissociation; Aldehyde intermediate transformation; Catalytic oxidation; H2O dissociation; Core-shell Pd@CoO Janus; Acetone
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2024.124113

Reactivity loss by intermediates aggregation and water vapor inhibition are two major and longstanding challenges for the noble-metal-based catalysts in oxygenated volatile organic compounds (OVOCs) oxidation. Herein, the core-shell Pd@CoO Janus sites are creatively designed and stabilized over the HSAPO-34 support. Quasi in situ XPS spectra reveal that the strong interactions in Pd@CoO Janus sites promote the charge redistribution and electron back-donation through Pd-O-Co coordination. Therefore, abundant positively charged Pd2+ sites are formed and oxygen species transformation is facilitated, which significantly promote the low-temperature efficiency of acetone oxidation. Furthermore, the Pd@CoO/HSAPO-34 catalyst facilitates H2O molecules dissociation and produce reactive OHTer and OHTri species, which considerably promotes the rapid decomposition of aldehyde intermediate via attacked CH2O* group, ensuring low-temperature oxidation of acetone. This work provides valuable guidance to develop specific catalysts with functional active sites for rationally utilizing H2O molecules to improve low-temperature performance and modulate reaction pathways during OVOCs oxidation. [Display omitted] •Thermal-depolymerization was employed to synthesize the Pd@CoO Janus sites.•Charge redistribution through Pd-O-Co coordination facilitates reactant activation.•Positively charged Pd2+ and activated Co-O coordination promote acetone oxidation.•Pd@CoO/HSAPO-34 catalyst facilitates the dissociation of H2O molecules.•Surface OHTri and OHTer groups accelerate aldehyde intermediate degradation.