--- _id: '7302' abstract: - lang: eng text: Understanding charge carrier transport in Li2O2, the storage material in the non-aqueous Li-O2 battery, is key to the development of this high-energy battery. Here, we studied ionic transport properties and Li self-diffusion in nanocrystalline Li2O2 by conductivity and temperature variable 7Li NMR spectroscopy. Nanostructured Li2O2, characterized by a mean crystallite size of less than 50 nm as estimated from X-ray diffraction peak broadening, was prepared by high-energy ball milling of microcrystalline lithium peroxide with μm sized crystallites. At room temperature the overall conductivity σ of the microcrystalline reference sample turned out to be very low (3.4 × 10−13 S cm−1) which is in agreement with results from temperature-variable 7Li NMR line shape measurements. Ball-milling, however, leads to an increase of σ by approximately two orders of magnitude (1.1 × 10−10 S cm−1); correspondingly, the activation energy decreases from 0.89 eV to 0.82 eV. The electronic contribution σeon, however, is in the order of 9 × 10−12 S cm−1 which makes less than 10% of the total value. Interestingly, 7Li NMR lines of nano-Li2O2 undergo pronounced heterogeneous motional narrowing which manifests in a two-component line shape emerging with increasing temperatures. Most likely, the enhancement in σ can be traced back to the generation of a spin reservoir with highly mobile Li ions; these are expected to reside in the nearest neighbourhood of defects generated or near the structurally disordered and defect-rich interfacial regions formed during mechanical treatment. article_processing_charge: No article_type: original author: - first_name: A. full_name: Dunst, A. last_name: Dunst - first_name: V. full_name: Epp, V. last_name: Epp - first_name: I. full_name: Hanzu, I. last_name: Hanzu - first_name: Stefan Alexander full_name: Freunberger, Stefan Alexander id: A8CA28E6-CE23-11E9-AD2D-EC27E6697425 last_name: Freunberger orcid: 0000-0003-2902-5319 - first_name: M. full_name: Wilkening, M. last_name: Wilkening citation: ama: Dunst A, Epp V, Hanzu I, Freunberger SA, Wilkening M. Short-range Li diffusion vs. long-range ionic conduction in nanocrystalline lithium peroxide Li2O2—the discharge product in lithium-air batteries. Energy & Environmental Science. 2014;7(8):2739-2752. doi:10.1039/c4ee00496e apa: Dunst, A., Epp, V., Hanzu, I., Freunberger, S. A., & Wilkening, M. (2014). Short-range Li diffusion vs. long-range ionic conduction in nanocrystalline lithium peroxide Li2O2—the discharge product in lithium-air batteries. Energy & Environmental Science. RSC. https://doi.org/10.1039/c4ee00496e chicago: Dunst, A., V. Epp, I. Hanzu, Stefan Alexander Freunberger, and M. Wilkening. “Short-Range Li Diffusion vs. Long-Range Ionic Conduction in Nanocrystalline Lithium Peroxide Li2O2—the Discharge Product in Lithium-Air Batteries.” Energy & Environmental Science. RSC, 2014. https://doi.org/10.1039/c4ee00496e. ieee: A. Dunst, V. Epp, I. Hanzu, S. A. Freunberger, and M. Wilkening, “Short-range Li diffusion vs. long-range ionic conduction in nanocrystalline lithium peroxide Li2O2—the discharge product in lithium-air batteries,” Energy & Environmental Science, vol. 7, no. 8. RSC, pp. 2739–2752, 2014. ista: Dunst A, Epp V, Hanzu I, Freunberger SA, Wilkening M. 2014. Short-range Li diffusion vs. long-range ionic conduction in nanocrystalline lithium peroxide Li2O2—the discharge product in lithium-air batteries. Energy & Environmental Science. 7(8), 2739–2752. mla: Dunst, A., et al. “Short-Range Li Diffusion vs. Long-Range Ionic Conduction in Nanocrystalline Lithium Peroxide Li2O2—the Discharge Product in Lithium-Air Batteries.” Energy & Environmental Science, vol. 7, no. 8, RSC, 2014, pp. 2739–52, doi:10.1039/c4ee00496e. short: A. Dunst, V. Epp, I. Hanzu, S.A. Freunberger, M. Wilkening, Energy & Environmental Science 7 (2014) 2739–2752. date_created: 2020-01-15T12:17:43Z date_published: 2014-08-01T00:00:00Z date_updated: 2021-01-12T08:12:53Z day: '01' doi: 10.1039/c4ee00496e extern: '1' intvolume: ' 7' issue: '8' language: - iso: eng month: '08' oa_version: Published Version page: 2739-2752 publication: Energy & Environmental Science publication_identifier: issn: - 1754-5692 - 1754-5706 publication_status: published publisher: RSC quality_controlled: '1' status: public title: Short-range Li diffusion vs. long-range ionic conduction in nanocrystalline lithium peroxide Li2O2—the discharge product in lithium-air batteries type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 7 year: '2014' ...