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Catalytic effect of laser-combined atmospheric pressure plasma in lowering the reduction temperature of hematite.

ABSTRACT: Atmospheric pressure plasma (APP) generates highly reactive species that are useful for surface activation. We demonstrate a fast regeneration of iron oxides, that are popular catalysts in various industrial processes, using microwave-driven argon APP under ambient conditions. The surface treatment of hematite powder by the APP with a small portion of hydrogen (0.5 vol%) lowers the oxide's reduction temperature. A near-infrared laser is used for localized heating to control the surface temperature. Controlled experiments without plasma confirm the catalytic effect of the plasma. Raman, XRD, SEM, and XPS analyses show that the plasma treatment changed the chemical state of the hematite to that of magnetite without sintering.

SUBMITTER: Yoo J

PROVIDER: S-EPMC9043150 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Catalytic effect of laser-combined atmospheric pressure plasma in lowering the reduction temperature of hematite.

Yoo Jaemin J Lee Dongkyu D Lee Jimo J Kim Taehyeong T Jin Hyungyu H Yun Gunsu S GS

RSC advances 20211001 56

Atmospheric pressure plasma (APP) generates highly reactive species that are useful for surface activation. We demonstrate a fast regeneration of iron oxides, that are popular catalysts in various industrial processes, using microwave-driven argon APP under ambient conditions. The surface treatment of hematite powder by the APP with a small portion of hydrogen (0.5 vol%) lowers the oxide's reduction temperature. A near-infrared laser is used for localized heating to control the surface temperatu ...[more]

PMID: 35493145

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Dataset Information

Catalytic effect of laser-combined atmospheric pressure plasma in lowering the reduction temperature of hematite.

Publications

Catalytic effect of laser-combined atmospheric pressure plasma in lowering the reduction temperature of hematite.

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