Work

Metal–Support Interaction in In2O3-Based Catalysts of CO2 Hydrogenation Studied Using “Inverse” In2O3(111)/Ru(0001) Model Systems

Year: 2025

Type: article

Abstract: High Resolution Image Download MS PowerPoint Slide Indium oxide (In 2 O 3 ) has recently received considerable attention in the catalysis community due to its unexpectedly high selectivity in the hydrogenation of CO 2 to methanol. Metal deposition onto In 2 O 3 substantially promotes the activity, while the selectivity remains close to that of bare In 2 O 3, independent of the metal used. To get insight into the metal/In 2 O 3 interaction and the role of the metal/oxide interface in the CO 2 hydrogenation reaction, we carried out a near-ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) study of “inverse” model catalysts prepared by In(III) oxide deposition onto a Ru(0001) substrate. Bulk-like In 2 O 3 (111) islands grow on the Ru(0001) surface at the onset of the deposition, and a continuous film is obtained above 5–7 nm of the nominal thickness. NAP-XPS measurements of the In 2 O 3 (111) films of various film thickness revealed the formation of metallic In(0) species at 200–280 °C in pure H 2 and CO 2 + H 2 atmospheres if In 2 O 3 partially covers the Ru surface but not on the continuous films. Moreover, these species formed in the H 2 containing ambient are altered considerably in the post-reaction samples, highlighting the necessity of operando studies on In 2 O 3 -based catalysts. Obviously, the In(0) formation is assisted by facile H 2 dissociation on the Ru surface, with H adatoms reacting at the interface to In 2 O 3 . XPS results obtained for reference systems prepared by direct In deposition showed that metallic In(0) formed in the H 2 atmosphere remains at the In 2 O 3 /Ru interface and does not migrate onto Ru to form a surface alloy.

Source: The Journal of Physical Chemistry C

DOI: 10.1021/acs.jpcc.5c00272

Authors: Jette K. Mathiesen, Jie Zhu, Weiming Wan, Shamil Shaikhutdinov, Beatriz Roldan Cuenya

Institution: Fritz Haber Institute of the Max Planck Society

Language: English

Topic: Catalysts for Methane Reforming

Subfield: Catalysis

Field: Chemical Engineering

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $4,500