Probing surface-sensitive redox properties of VOx/TiO2 catalyst nanoparticles
Journal article, 2021
Redox processes of oxide materials are fundamental in catalysis. These processes depend on the surface structure and stoichiometry of the oxide and are therefore expected to vary between surface facets. However, there is a lack of direct measurements of redox properties on the nanoscale for analysing the importance of such faceting effects in technical materials. Here, we address the facet-dependent redox properties of vanadium-oxide-covered anatase nanoparticles of relevance to, e.g., selective catalytic reduction of nitrogen oxides. The vanadium oxidation states at individual nanoscale facets are resolved in situ under catalytically relevant conditions by combining transmission electron microscopy imaging and electron energy loss spectroscopy. The measurements reveal that vanadium on {001} facets consistently retain higher oxidation states than on {10l} facets. Insight into such structure-sensitivity of surface redox processes opens prospects of tailoring oxide nanoparticles with enhanced catalytic functionalities.
Author
Martin Ek
Chalmers, Physics, Eva Olsson Group
Haldor Topsoe
Competence Centre for Catalysis (KCK)
Logi Arnarson
Haldor Topsoe
Poul Georg Moses
Haldor Topsoe
Soren B. Rasmussen
Haldor Topsoe
Magnus Skoglundh
Competence Centre for Catalysis (KCK)
Chalmers, Chemistry and Chemical Engineering, Applied Chemistry
Eva Olsson
Chalmers, Physics, Nano and Biophysics
Competence Centre for Catalysis (KCK)
Stig Helveg
Technical University of Denmark (DTU)
Haldor Topsoe
Nanoscale
2040-3364 (ISSN) 2040-3372 (eISSN)
Vol. 13 15 7266-7272Subject Categories
Inorganic Chemistry
Materials Chemistry
Other Chemistry Topics
DOI
10.1039/d0nr08943e
PubMed
33889890