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Formation mechanism of Mn _x Co_3-x O₄ yolk-shell structures.

ABSTRACT: Formation of Mn _x Co_3-x O₄ yolk-shell microspheres via a solvothermal reaction of hydrated cobalt and manganese nitrates in ethanol is investigated. Spinel nanocrystals of cobalt oxide or cobalt-rich ternary oxide preferentially develop in the system, while manganese-rich hydroxide form Mn(OH)₂-type nanosheets. Instead of continuing to grow individually, the nanocrystallites and nanosheets aggregate into large microspheres due to their strong inter-particle interaction. When the proportion of Mn-rich nanosheets is high, therefore the overall density is low, dehydration of hydroxide nanosheets and a surface re-crystallisation lead to formation of a dense and rigid shell, which is separated from a solid or hollow core via a further Ostwald ripening process. The proposed formation mechanism of the yolk-shell structures based on electron microscopic studies would help us to develop yolk-shell structure based multifunctional materials.

SUBMITTER: Chiang CY

PROVIDER: S-EPMC9040891 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

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Formation mechanism of Mn x Co3-x O4 yolk-shell structures.

Chiang Chang-Yang CY Zhou Wuzong W

RSC advances 20210901 47

Formation of Mn x Co3-x O4 yolk-shell microspheres via a solvothermal reaction of hydrated cobalt and manganese nitrates in ethanol is investigated. Spinel nanocrystals of cobalt oxide or cobalt-rich ternary oxide preferentially develop in the system, while manganese-rich hydroxide form Mn(OH)2-type nanosheets. Instead of continuing to grow individually, the nanocrystallites and nanosheets aggregate into large microspheres due to t ...[more]

PMID: 35479530

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