Activation of CO<inf>2</inf> at chromia-nanocluster-modified rutile and anatase TiO<inf>2</inf>

Nolan, M; Fronzi, M

Activation of CO<inf>2</inf> at chromia-nanocluster-modified rutile and anatase TiO<inf>2</inf>

Nolan, M Fronzi, M

Permalink

Publication Type:: Journal Article
Citation:: Catalysis Today, 2019, 326 pp. 68 - 74
Issue Date:: 2019-04-01

Closed Access

	Filename	Description	Size
	CatTod2019.pdf	Published Version	3.53 MB	Adobe PDF	View/Open

Copyright Clearance Process

Recently Added
In Progress
Closed Access

This item is closed access and not available.

Full metadata record

Field	Value	Language
dc.contributor.author	Nolan, M	en_US
dc.contributor.author	Fronzi, M https://orcid.org/0000-0001-7855-9216	en_US
dc.date.issued	2019-04-01	en_US
dc.identifier.citation	Catalysis Today, 2019, 326 pp. 68 - 74	en_US
dc.identifier.issn	0920-5861	en_US
dc.identifier.uri	http://hdl.handle.net/10453/131865
dc.description.abstract	© 2018 Elsevier B.V. Converting CO2 to fuels is required to enable the production of sustainable fuels and to contribute to alleviating CO2 emissions. In considering conversion of CO2, the initial step of adsorption and activation by the catalyst is crucial. In addressing this difficult problem, we have examined how nanoclusters of reducible metal oxides supported on TiO2 can promote CO2 activation. In this paper we present density functional theory (DFT) simulations of CO2 activation on heterostructures composed of clean or hydroxylated extended rutile and anatase TiO2 surfaces modified with chromia nanoclusters. The heterostructures show non-bulk Cr and O sites in the nanoclusters and an upshifted valence band edge that is dominated by Cr 3d- O 2p interactions. We show that the supported chromia nanoclusters can adsorb and activate CO2 and that activation of CO2 is promoted whether the TiO2 support is oxidised or hydroxylated. Reduced heterostructures, formed by removal of oxygen from the chromia nanocluster, also promote CO2 activation. In the strong CO2 adsorption modes, the molecule bends giving O–C–O angles of 127 - 132° and elongation of C–O distances up to 1.30 Å; no carbonates are formed. The electronic properties show a strong CO2–Cr–O interaction that drives the interaction of CO2 with the nanocluster and induces the structural distortions. These results highlight that a metal oxide support modified with reducible metal oxide nanoclusters can activate CO2, thus helping to overcome difficulties associated with the difficult first step in CO2 conversion.	en_US
dc.relation.ispartof	Catalysis Today	en_US
dc.relation.isbasedon	10.1016/j.cattod.2018.11.062	en_US
dc.subject.classification	Physical Chemistry	en_US
dc.title	Activation of CO<inf>2</inf> at chromia-nanocluster-modified rutile and anatase TiO<inf>2</inf>	en_US
dc.type	Journal Article
utslib.citation.volume	326	en_US
utslib.for	0306 Physical Chemistry (incl. Structural)	en_US
utslib.for	0904 Chemical Engineering	en_US
utslib.for	03 Chemical Sciences	en_US
utslib.for	09 Engineering	en_US
pubs.embargo.period	Not known	en_US
pubs.organisational-group	/University of Technology Sydney
pubs.organisational-group	/University of Technology Sydney/Faculty of Science
utslib.copyright.status	closed_access
pubs.publication-status	Published	en_US
pubs.volume	326	en_US

Abstract:

© 2018 Elsevier B.V. Converting CO2 to fuels is required to enable the production of sustainable fuels and to contribute to alleviating CO2 emissions. In considering conversion of CO2, the initial step of adsorption and activation by the catalyst is crucial. In addressing this difficult problem, we have examined how nanoclusters of reducible metal oxides supported on TiO2 can promote CO2 activation. In this paper we present density functional theory (DFT) simulations of CO2 activation on heterostructures composed of clean or hydroxylated extended rutile and anatase TiO2 surfaces modified with chromia nanoclusters. The heterostructures show non-bulk Cr and O sites in the nanoclusters and an upshifted valence band edge that is dominated by Cr 3d- O 2p interactions. We show that the supported chromia nanoclusters can adsorb and activate CO2 and that activation of CO2 is promoted whether the TiO2 support is oxidised or hydroxylated. Reduced heterostructures, formed by removal of oxygen from the chromia nanocluster, also promote CO2 activation. In the strong CO2 adsorption modes, the molecule bends giving O–C–O angles of 127 - 132° and elongation of C–O distances up to 1.30 Å; no carbonates are formed. The electronic properties show a strong CO2–Cr–O interaction that drives the interaction of CO2 with the nanocluster and induces the structural distortions. These results highlight that a metal oxide support modified with reducible metal oxide nanoclusters can activate CO2, thus helping to overcome difficulties associated with the difficult first step in CO2 conversion.

Please use this identifier to cite or link to this item:

http://hdl.handle.net/10453/131865