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Electric Field and Mobile Oxygen Promote Low-Temperature Oxidative Coupling of Methane over La_1-x Ca _x AlO_3-? Perovskite Catalysts.

ABSTRACT: Oxidative coupling of methane (OCM) over La_1-x M _x AlO_3-? (M = Ca, Sr, Ba; x = 0, 0.1, 0.2, 0.3) in an electric field at low temperature (423 K) was investigated. Among the tested catalysts, the La_0.7Ca_0.3AlO_3-? catalyst showed the highest performance in terms of C₂H₆ + C₂H₄ yield (11.1%). Surface mobile oxygen species (O₂ ^2- or O^-), which were considered as active oxygen species for the OCM reaction, increased with increasing Ca doping amount, and thereby the La_0.7Ca_0.3AlO_3-? catalyst showed the best catalytic activity.

SUBMITTER: Sato A

PROVIDER: S-EPMC6648777 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Electric Field and Mobile Oxygen Promote Low-Temperature Oxidative Coupling of Methane over La1-x Ca x AlO3-δ Perovskite Catalysts.

Sato Ayaka A Ogo Shuhei S Takeno Yuna Y Takise Kent K Seo Jeong Gil JG Sekine Yasushi Y

ACS omega 20190617 6

Oxidative coupling of methane (OCM) over La1-x M x AlO3-δ (M = Ca, Sr, Ba; x = 0, 0.1, 0.2, 0.3) in an electric field at low temperature (423 K) was investigated. Among the tested catalysts, the La0.7Ca0.3AlO3-δ catalyst showed the highest performance in terms of C2H6 + C2H4 yield (11.1%). Surface mobile oxygen species (O2 2- or O-), ...[more]

PMID: 31460139

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