Support induced effects on the ir nanoparticles activity, selectivity and stability performance under CO<inf>2</inf> reforming of methane

Nikolaraki, Ersi; Goula, Grammatiki; Panagiotopoulo, Paraskevi; Taylor, Martin J.; Kousi, Kalliopi; Kyriakou, Georgios; Kondarides, Dimitris I.; Lambert, Richard M.; Yentekakis, Ioannis V.

Abstract

The production of syngas (H2 and CO)—a key building block for the manufacture of liquid energy carriers, ammonia and hydrogen—through the dry (CO2 −) reforming of methane (DRM) continues to gain attention in heterogeneous catalysis, renewable energy technologies and sustainable economy. Here we report on the effects of the metal oxide support (γ-Al2 O3, alumina-ceria-zirconia (ACZ) and ceria-zirconia (CZ)) on the low-temperature (ca. 500–750◦ C) DRM activity, selectivity, resistance against carbon deposition and iridium nanoparticles sintering under oxidative thermal aging. A variety of characterization techniques were implemented to provide insight into the factors that determine iridium intrinsic DRM kinetics and stability, including metal-support interactions and physicochemical properties of materials. All Ir/γ-Al2 O3, Ir/ACZ and Ir/CZ catalysts have stable DRM performance with time-on-stream, although supports with high oxygen storage capacity (ACZ and CZ) promoted CO2 conversion, yielding CO-enriched syngas. CZ-based supports endow Ir exceptional anti-sintering characteristics. The amount of carbon deposition was small in all catalysts, however decreasing as Ir/γ-Al2 O3 > Ir/ACZ > Ir/CZ. The experimental findings are consistent with a bifunctional reaction mechanism involving participation of oxygen vacancies on the support’s surface in CO2 activation and carbon removal, and overall suggest that CZ-supported Ir nanoparticles are promising catalysts for low-temperature dry reforming of methane (LT-DRM).

Citation

Nikolaraki, E., Goula, G., Panagiotopoulo, P., Taylor, M. J., Kousi, K., Kyriakou, G., …Yentekakis, I. V. (2021). Support induced effects on the ir nanoparticles activity, selectivity and stability performance under CO2 reforming of methane. Nanomaterials, 11(11), Article 2880. https://doi.org/10.3390/nano11112880

• Journal Article Type: Article
• Acceptance Date: Oct 25, 2021
• Online Publication Date: Oct 28, 2021
• Publication Date: Nov 1, 2021
• Deposit Date: Oct 29, 2021
• Publicly Available Date: Oct 29, 2021
• Journal: Nanomaterials
• Print ISSN: 2079-4991
• Electronic ISSN: 2079-4991
• Publisher: MDPI
• Peer Reviewed: Peer Reviewed
• Volume: 11
• Issue: 11
• Article Number: 2880
• DOI: https://doi.org/10.3390/nano11112880
• Keywords: Greenhouse gases; Dry reforming of methane; Carbon dioxide; Alumina-ceria-zirconia mixed oxides; Iridium nanoparticles; Coking-resistant catalysts; Sintering-resistant catalysts; Syngas production
• Public URL: https://hull-repository.worktribe.com/output/3865403
• Publisher URL: https://www.mdpi.com/2079-4991/11/11/2880