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The current research on cation-intercalation and conversion-type cathode materials for rechargeable aluminum batteries (RABs) is discussed in this critical review. The experimental evidence for Al 3+ intercalation in transition metal oxides, chalcogenides, MXene, and Prussian blue analogues in both chloroaluminate ionic liquids and aqueous electrolytes is analyzed to identify the true reaction mechanisms. Chevrel phase molybdenum sulfide (Mo 6 S 8 ) is the only proven intercalation material for RABs with unambiguous evidence, different understandings of the Al 3+ intercalation mechanism in Mo 6 S 8 are discussed. For conversion-type cathode materials, the discussion is focused on the conversion mechanism of metal chalcogenides, and the unique reversible oxidation mechanism of sulfur and selenium enabled by the chloroaluminate ionic liquid electrolytes. The reaction mechanisms of organic cathode materials are also discussed.
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In Situ TEM Study on Conversion‐Type Electrodes for Rechargeable Ion Batteries
Abstract Conversion‐type materials have been considered as potentially high‐energy‐density alternatives to commercially dominant intercalation‐based electrodes for rechargeable ion batteries and have attracted tremendous research effort to meet the performance for viable energy‐storage technologies. In situ transmission electron microscopy (TEM) has been extensively employed to provide mechanistic insights into understanding the behavior of battery materials. Noticeably, a great portion of previous in situ TEM studies has been focused on conversion‐type materials, but a dedicated review for this group of materials is missing in the literature. Herein, recent developments of in situ TEM techniques for investigation of dynamic phase transformation and associated structural, morphological, and chemical evolutions during conversion reactions with alkali ions in secondary batteries are comprehensively summarized. The materials of interest broadly cover metal oxides, chalcogenides, fluorides, phosphides, nitrides, and silicates with specific emphasis on spinel metal oxides and recently emerged 2D metal chalcogenides. Special focus is placed on the scientific findings that are uniquely obtained by in situ TEM to address fundamental questions and practical issues regarding phase transformation, structural evolution, electrochemical redox, reaction mechanism, kinetics, and degradation. Critical challenges and perspectives are discussed for advancing new knowledge that can bridge the gap between prototype materials and real‐world applications.
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- Award ID(s):
- 1929138
- PAR ID:
- 10453940
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 33
- Issue:
- 6
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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