{"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."}],"publication":"Energy & Environmental Science","article_processing_charge":"No","publisher":"RSC","quality_controlled":"1","publication_status":"published","volume":7,"status":"public","title":"Short-range Li diffusion vs. long-range ionic conduction in nanocrystalline lithium peroxide Li2O2—the discharge product in lithium-air batteries","publication_identifier":{"issn":["1754-5692","1754-5706"]},"date_updated":"2021-01-12T08:12:53Z","intvolume":"         7","language":[{"iso":"eng"}],"article_type":"original","oa_version":"Published Version","author":[{"first_name":"A.","last_name":"Dunst","full_name":"Dunst, A."},{"last_name":"Epp","first_name":"V.","full_name":"Epp, V."},{"first_name":"I.","last_name":"Hanzu","full_name":"Hanzu, I."},{"first_name":"Stefan Alexander","last_name":"Freunberger","id":"A8CA28E6-CE23-11E9-AD2D-EC27E6697425","orcid":"0000-0003-2902-5319","full_name":"Freunberger, Stefan Alexander"},{"first_name":"M.","last_name":"Wilkening","full_name":"Wilkening, M."}],"date_created":"2020-01-15T12:17:43Z","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","extern":"1","type":"journal_article","date_published":"2014-08-01T00:00:00Z","month":"08","day":"01","_id":"7302","citation":{"short":"A. Dunst, V. Epp, I. Hanzu, S.A. Freunberger, M. Wilkening, Energy &#38; Environmental Science 7 (2014) 2739–2752.","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 &#38; Environmental Science. 7(8), 2739–2752.","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.” <i>Energy &#38; Environmental Science</i>. RSC, 2014. <a href=\"https://doi.org/10.1039/c4ee00496e\">https://doi.org/10.1039/c4ee00496e</a>.","apa":"Dunst, A., Epp, V., Hanzu, I., Freunberger, S. A., &#38; Wilkening, M. (2014). Short-range Li diffusion vs. long-range ionic conduction in nanocrystalline lithium peroxide Li2O2—the discharge product in lithium-air batteries. <i>Energy &#38; Environmental Science</i>. RSC. <a href=\"https://doi.org/10.1039/c4ee00496e\">https://doi.org/10.1039/c4ee00496e</a>","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.” <i>Energy &#38; Environmental Science</i>, vol. 7, no. 8, RSC, 2014, pp. 2739–52, doi:<a href=\"https://doi.org/10.1039/c4ee00496e\">10.1039/c4ee00496e</a>.","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,” <i>Energy &#38; Environmental Science</i>, vol. 7, no. 8. RSC, pp. 2739–2752, 2014.","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. <i>Energy &#38; Environmental Science</i>. 2014;7(8):2739-2752. doi:<a href=\"https://doi.org/10.1039/c4ee00496e\">10.1039/c4ee00496e</a>"},"year":"2014","doi":"10.1039/c4ee00496e","page":"2739-2752","issue":"8"}