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Catalytic Co-Conversion of CH₄ and CO₂ Mediated by Rhodium-Titanium Oxide Anions RhTiO₂.

ABSTRACT: Catalytic co-conversion of methane with carbon dioxide to produce syngas (2 H₂ +2 CO) involves complicated elementary steps and almost all the elementary reactions are performed at the same high temperature conditions in practical thermocatalysis. Here, we demonstrate by mass spectrometric experiments that RhTiO₂ ^- promotes the co-conversion of CH₄ and CO₂ to free 2 H₂ +CO and an adsorbed CO (CO_ads ) at room temperature; the only elementary step that requires the input of external energy is desorption of CO_ads from the RhTiO₂ CO^- to reform RhTiO₂ ^- . This study not only identifies a promising active species for dry (CO₂ ) reforming of methane to syngas, but also emphasizes the importance of temperature control over elementary steps in practical catalysis, which may significantly alleviate the carbon deposition originating from the pyrolysis of methane.

SUBMITTER: Yang Y

PROVIDER: S-EPMC8251526 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Catalytic Co-Conversion of CH4 and CO2 Mediated by Rhodium-Titanium Oxide Anions RhTiO2.

Yang Yuan Y Li Ya-Ke YK Zhao Yan-Xia YX Wei Gong-Ping GP Ren Yi Y Asmis Knut R KR He Sheng-Gui SG

Angewandte Chemie (International ed. in English) 20210517 25

Catalytic co-conversion of methane with carbon dioxide to produce syngas (2 H2 +2 CO) involves complicated elementary steps and almost all the elementary reactions are performed at the same high temperature conditions in practical thermocatalysis. Here, we demonstrate by mass spectrometric experiments that RhTiO2 - promotes the co-conversion of CH4 and CO2 to free 2 H2 +CO and an adsorbed CO (COads ) at room temperature ...[more]

PMID: 33890352

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