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Investigation of Photoexcited Carrier Dynamics in Hematite and the Effect of Surface Modifications by an Advanced Transient Grating Technique.

ABSTRACT: Photoexcited carrier dynamics in a hematite film with and without amorphous NiFeO _x on the surface was investigated using the heterodyne transient grating method. We found that two different electron/hole dynamics took place in the micro- and millisecond time regions and successfully assigned each component to the decay processes of electrons and holes trapped at surface states, respectively. It was also demonstrated that the amorphous NiFeO _x coating plays a crucial role in increasing the survival of the holes at the surface trap states, which was caused by the decrease in the surface recombination rate.

SUBMITTER: Sohn WY

PROVIDER: S-EPMC6640961 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Investigation of Photoexcited Carrier Dynamics in Hematite and the Effect of Surface Modifications by an Advanced Transient Grating Technique.

Sohn Woon Yong WY Kuwahara Shota S Thorne James E JE Wang Dunwei D Katayama Kenji K

ACS omega 20170317 3

Photoexcited carrier dynamics in a hematite film with and without amorphous NiFeO x on the surface was investigated using the heterodyne transient grating method. We found that two different electron/hole dynamics took place in the micro- and millisecond time regions and successfully assigned each component to the decay processes of electrons and holes trapped at surface states, respectively. It was also demonstrated that the amorphous NiFeO x coating plays a ...[more]

PMID: 31457484

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