In:
Physical Chemistry Chemical Physics, Royal Society of Chemistry (RSC), Vol. 25, No. 22 ( 2023), p. 15547-15554
Abstract:
Lanthanum oxide (La 2 O 3 ) possesses superior reactivity during catalytic hydrogenation, but the intrinsic activity of La 2 O 3 toward H 2 adsorption and activation remains unclear. In the present work, we fundamentally investigated hydrogen interaction with Ni-modified La 2 O 3 . Hydrogen temperature programmed desorption (H 2 -TPD) on Ni/La 2 O 3 shows enhanced hydrogen adsorption with a new hydrogen desorption peak at a higher temperature position compared to that on the metallic Ni surfaces. By systematically exploring the desorption experiments, the enhanced H 2 adsorption on Ni/La 2 O 3 is due to the oxygen vacancies formed at the metal–oxide interfaces. Hydrogen atoms transfer from Ni surfaces to the oxygen vacancies to form lanthanum oxyhydride species (H–La–O) at the metal–oxide interfaces. The adsorbed hydrogen at the metal–oxide interfaces of Ni/La 2 O 3 results in improved catalytic reactivity in CO 2 methanation. Furthermore, the enhanced hydrogen adsorption on the interfacial oxygen vacancies is ubiquitous for La 2 O 3 -supported Fe, Co, and Ni nanoparticles. Benefiting from the modification effect of the supported transition metal nanoparticles, the surface oxyhydride species can be formed on La 2 O 3 surfaces, which resembles the recently reported oxyhydride observed on the reducible CeO 2 surfaces with abundant surface oxygen vacancies. These findings strengthen our understanding of the surface chemistry of La 2 O 3 and shed new light on the design of highly efficient La 2 O 3 -based catalysts with metal–oxide interfaces.
Type of Medium:
Online Resource
ISSN:
1463-9076
,
1463-9084
Language:
English
Publisher:
Royal Society of Chemistry (RSC)
Publication Date:
2023
detail.hit.zdb_id:
1476283-3
detail.hit.zdb_id:
1476244-4
detail.hit.zdb_id:
1460656-2
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