open access

https://hdl.handle.net/2115/97386

Ultrasmall α-MnO2 with Low Aspect Ratio : Applications to Electrochemical Multivalent-Ion Intercalation Hosts and Aerobic Oxidation Catalysts

英語

nanoparticle

2025-01-16

Wiley-Blackwell

Small

21(7)

Hollandite-type alpha-MnO2 exhibits exceptional promise in current industrial applications and in advancing next-generation green energy technologies, such as multivalent (Mg2+, Ca2+, and Zn2+) ion battery cathodes and aerobic oxidation catalysts. Considering the slow diffusion of multivalent cations within alpha-MnO2 tunnels and the catalytic activity at edge surfaces, ultrasmall alpha-MnO2 particles with a lower aspect ratio are expected to unlock the full potential. In this study, ultrasmall alpha-MnO2 (<10 nm) with a low aspect ratio (c/a approximate to 2) is synthesized using a newly developed alcohol solution process. This material demonstrates exceptional performance across various multivalent battery systems, primarily due to the significantly reduced cation diffusion distance. Notably, an ultrasmall alpha-MnO2-graphene composite achieves high capacity with low overpotential when paired with an F-free electrolyte in Ca battery. Regarding aerobic oxidation catalysis, the nanosizing of alpha-MnO2 has a profound impact on aerobic oxidation catalysis. The increased efficiency of oxidative conversion reactions, such as the oxidation of 1-phenylethanol, is attributed to the greatly expanded active surface area of the catalyst. The versatile functionality of ultrasmall alpha-MnO2 underscores its potential to revolutionize energy storage and catalysis, offering broad applicability in next-generation green energy technologies.

学術雑誌論文

Accepted Manuscript

This is the peer reviewed version of the following article: Ultrasmall α-MnO2 with Low Aspect Ratio: Applications to Electrochemical Multivalent-Ion Intercalation Hosts and Aerobic Oxidation Catalysts, which has been published in final form at https://doi.org/10.1002/smll.202411493. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited.

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