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Room-Temperature Activation of CO2 by Dual Defect-Stabilized Nanoscale Hematite (Fe2-?O3-v ): Concurrent Role of Fe and O Vacancies.

ABSTRACT: We demonstrate that synthetically controlled concurrent stabilization of Fe and O vacancy defects on the surface of interbraided nanoscale hematite (Fe2-?O3-v ) renders an interesting surface chemistry which can reduce CO2 to CO at room temperature (RT). Importantly, we realized a highly enhanced output of 410 ?mol h-1 g-1 at RT, as compared to that of 10 ?mol h-1 g-1 for bulk hematite. It is argued based on the activity degradation under cycling and first principles density functional theory calculations that the excess chemical energy embedded in the defect-stabilized surface is expended in this high-energy conversion process, which leads to progressive filling up of oxygen vacancies.

SUBMITTER: Nagaraju D

PROVIDER: S-EPMC6645434 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Room-Temperature Activation of CO2 by Dual Defect-Stabilized Nanoscale Hematite (Fe2-δO3-v ): Concurrent Role of Fe and O Vacancies.

Nagaraju Divya D Gupta Sharad S Kumar Deepak D Jijil Chamundi P CP Bhat Suresh K SK Jagadeesan Dinesh D Ogale Satishchandra S

ACS omega 20171129 11

We demonstrate that synthetically controlled concurrent stabilization of Fe and O vacancy defects on the surface of interbraided nanoscale hematite (Fe2-δO3-v ) renders an interesting surface chemistry which can reduce CO2 to CO at room temperature (RT). Importantly, we realized a highly enhanced output of 410 μmol h-1 g-1 at RT, as compared to that of 10 μmol h-1 g-1 for bulk hematite. It is argued based on the ...[more]

PMID: 31457379

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