Exploring the impact of nanoshaped ceria in the methanol decomposition reaction pathway for clean energy production

Highlights

• Different Pd/CeO₂ nanoshapes were synthesized and tested in methanol decomposition reaction.
• The structure sensitive nature of methanol decomposition reaction has been demonstrated.
• Different reaction pathways were elucidated depending on the facet exposed by a Pd/CeO₂ catalyst.

Abstract

The effect of facet exposure in ceria nanostructures on the catalytic properties of Pd/CeO₂ during methanol decomposition was investigated. The results showed the structure sensitive nature of this reaction, with the catalytic activity depending on the facet exposed in the ceria nanostructures. Operando DRIFTS-MS and DFT calculations demonstrated that methanol decomposition proceeds mainly via two reaction pathways depending on the exposed nanofacets: the formate and the formaldehyde pathways. The formaldehyde pathway is inhibited on the (111) nanofacets, where only the formate pathway is energetically favoured, in contrast to the (100) and (110) facets. Superior specific catalytic activity was observed in the catalyst with octahedral morphology, attributed to the higher number of oxygen vacancies per unit surface area, which facilitates the decomposition of formates. By gaining a better understanding of the relationship between the shape control of the catalyst, this work contributes to the collective effort of discovering and implementing sustainable low-carbon energy solutions.