Morphology effect of ceria support with hierarchical structure on the catalytic performance for nickel-based catalysts in dry reforming of methane

Abstract

CeO2 is widely used as Ni-based catalyst support in methane dry reforming (DRM), and the hierarchical structure of the ceria behaves a favorable effect on the performance of the catalyst. Ceria with different morphologies, including dumbbell (CeO2-D), bouquet (CeO2-B) and shuttle (CeO2-S) shapes, are hydrothermally prepared, and the effect of ceria shape on the catalytic performance of Ni/CeO2 in DRM is investigated by a fixed-bed tubular reactor. The results indicate that Ni/CeO2-D demonstrates the best reaction conversions & TOF value, whose conversions of CH4 & CO2 can reach 92% & 87%, respectively. Furthermore, a series of characterization results (XPS, H2-TPR and Raman) confirm that the Ni/CeO2-D own the abundant oxygen vacancies and strong metal-support interaction, which promote the reactivity of CH4 and CO2, resulting in its most prominent catalytic performance. Additionally, Ni/CeO2-D possesses other distinct advantages due to its hierarchical dumbbell-like structure confirmed by high Ni dispersion (H2-TPD), abundant surface oxygen (H2-TPR) and sufficient basic sites (CO2-TPD).