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Multi-electron transfer enabled by topotactic reaction in magnetite.

ABSTRACT: A bottleneck for the large-scale application of today's batteries is low lithium storage capacity, largely due to the use of intercalation-type electrodes that allow one or less electron transfer per redox center. An appealing alternative is multi-electron transfer electrodes, offering excess capacity, which, however, involves conversion reaction; according to conventional wisdom, the host would collapse during the process, causing cycling instability. Here, we report real-time observation of topotactic reaction throughout the multi-electron transfer process in magnetite, unveiled by in situ single-crystal crystallography with corroboration of first principles calculations. Contradicting the traditional belief of causing structural breakdown, conversion in magnetite resembles an intercalation process-proceeding via topotactic reaction with the cubic close packed oxygen-anion framework retained. The findings from this study, with unique insights into enabling multi-electron transfer via topotactic reaction, and its implications to the cyclability and rate capability, shed light on designing viable multi-electron transfer electrodes for high energy batteries.

SUBMITTER: Zhang W

PROVIDER: S-EPMC6488677 | biostudies-other | 2019 Apr

REPOSITORIES: biostudies-other

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Multi-electron transfer enabled by topotactic reaction in magnetite.

Zhang Wei W Li Yan Y Wu Lijun L Duan Yandong Y Kisslinger Kim K Chen Chunlin C Bock David C DC Pan Feng F Zhu Yimei Y Marschilok Amy C AC Takeuchi Esther S ES Takeuchi Kenneth J KJ Wang Feng F

Nature communications 20190429 1

A bottleneck for the large-scale application of today's batteries is low lithium storage capacity, largely due to the use of intercalation-type electrodes that allow one or less electron transfer per redox center. An appealing alternative is multi-electron transfer electrodes, offering excess capacity, which, however, involves conversion reaction; according to conventional wisdom, the host would collapse during the process, causing cycling instability. Here, we report real-time observation of to ...[more]

PMID: 31036803

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Multi-electron transfer enabled by topotactic reaction in magnetite.

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Multi-electron transfer enabled by topotactic reaction in magnetite.

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