Vacancy-mediated Interfacial Charge Transfer in Au-ZnO by Fe promoter for low-temperature CO oxidation. Issue 2 (April 2022)

• Record Type: Journal Article
• Authors: Sarkodie, Bismark; Hu, Yanjie; Asinyo, Benjamin; Jiang, Jiechao; Tawiah, Benjamin; Li, Chunzhong
• Is Part Of: Journal of environmental chemical engineering. Volume 10:Issue 2(2022)
• Publication Date: 2022-04
• Subjects: FeOx/ZnO -- Ultrasonic spray pyrolysis -- Gold nanoparticles -- Electron transfer -- CO oxidation; Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2021.106651
• Languages: English
• ISSNs: 2213-2929

Abstract

Abstract: The charge transfer process existing at the metal-support interface of a catalyst is a crucial factor which could be augmented by the creation of vacancy defects. This study reveals the individual and combined effect of Au and Fe promoter in Au-FeO x /ZnO catalysts for CO oxidation. FeO x /ZnO were synthesized with a highly scalable spray pyrolysis method while Au was incorporated by deposition-precipitation strategy. The physicochemical characterization revealed that Fe promoter substituted into the ZnO created abundant oxygen vacancy defects, which favors the interaction of Au on FeO x /ZnO. The anchoring of Au on FeO x /ZnO support substantially enhance charge transfer from Au to support as compared to iron-free Au-ZnO catalyst. However, superfluous Fe load in Au-FeO x /ZnO led to change in structure and deterioration in metal-support interaction. The amelioration in catalytic performance of Au-FeO x /ZnO catalysts was accredited to the strong metal-support interaction and enhanced charge transfer sourcing from the vacancy-mediated Fe promoter in FeO x /ZnO. The optimal catalytic performance was reported on Au-FeO x /ZnO containing 20% which also exhibits good stability while further increment in Fe load reveals adverse effect on the catalytic activity. Graphical Abstract: ga1 Highlights: FeO x /ZnO support was prepared by facile ultrasonic spray pyrolysis. Surface active Au species on FeO x /ZnO was loaded by deposition-precipitation. Incorporation of FeO x into ZnO effectively created abundant vacancy defects. FeO x facilitated more electron transfer from Au species to FeO x /ZnO support. Full CO conversion was achieved on Au-FeO x /ZnO at 40 °C with good long-term stability.