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Polymorph selection towards photocatalytic gaseous CO₂ hydrogenation.

ABSTRACT: Titanium dioxide is the only known material that can enable gas-phase CO₂ photocatalysis in its anatase and rutile polymorphic forms. Materials engineering of polymorphism provides a useful strategy for optimizing the performance metrics of a photocatalyst. In this paper, it is shown that the less well known rhombohedral polymorph of indium sesquioxide, like its well-documented cubic polymorph, is a CO₂ hydrogenation photocatalyst for the production of CH₃OH and CO. Significantly, the rhombohedral polymorph exhibits higher activity, superior stability and improved selectivity towards CH₃OH over CO. These gains in catalyst performance originate in the enhanced acidity and basicity of surface frustrated Lewis pairs in the rhombohedral form.

SUBMITTER: Yan T

PROVIDER: S-EPMC6555785 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Polymorph selection towards photocatalytic gaseous CO2 hydrogenation.

Yan Tingjiang T Wang Lu L Liang Yan Y Makaremi Meysam M Wood Thomas E TE Dai Ying Y Huang Baibiao B Ali Feysal M FM Dong Yuchan Y Ozin Geoffrey A GA

Nature communications 20190607 1

Titanium dioxide is the only known material that can enable gas-phase CO2 photocatalysis in its anatase and rutile polymorphic forms. Materials engineering of polymorphism provides a useful strategy for optimizing the performance metrics of a photocatalyst. In this paper, it is shown that the less well known rhombohedral polymorph of indium sesquioxide, like its well-documented cubic polymorph, is a CO2 hydrogenation photocatalyst for the production of CH3OH and ...[more]

PMID: 31175311

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