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Updated: Sep 25, 2025
Manganese Oxide Nanoparticle Synthesis by Thermal Decomposition of ManganeseII Acetylacetonate
Published on: June 18, 2020
Formation mechanism of Mn Co3- O4 yolk-shell structures
Chang-Yang Chiang1, Wuzong Zhou1
1EaStChem, School of Chemistry, University of St Andrews Fife KY16 9ST UK wzhou@st-andrews.ac.uk.
Abstract:
Formation of Mn Co3- 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.
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