, Volume 25, Issue 2, pp 891–895 | Cite as

Mesoscopically enhanced ion conduction—claim without evidence

  • H. NäfeEmail author
Original Paper


The claim of enhanced ionic conductivity in CaF2-based thin-film composites due to a mesoscopic effect propagated in Nature 408 (2000) 946–949 is unsubstantiated because:

(i) The experimental approach to measure the conductivity does not provide information about the nature of the effective charge carriers

(ii) The interpretation of the findings ignores fundamental relations in solid-state electrochemistry on the interplay of ionic and electronic transport and disregards well-documented facts about the electrical and chemical properties of the materials concerned


Anionic conductors Electronic conductivities Hebb-Wagner Thin films Ionic conductivities 



The author wishes to thank the reviewers of this article for their helpful advice.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Institut für MaterialwissenschaftUniversität StuttgartStuttgartGermany

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