The effect of surface tension upon the activation energy for O-ion conduction in nanoceramics was considered. The activation energy for O-ion diffusion via O-vacancies (treated as dilatation centers) was calculated. The activation energy was shown to decrease as the nanoparticle size decreased. Based upon the size distribution function of nanoparticles, the activation energy distribution function was calculated. Analytical expressions were obtained for the dependences of ionic conduction upon temperature and nanoparticle size. An increase of 2 to 3 orders of magnitude in the O-ion conduction, observed earlier in ZrO2-16%Y nanoceramics, was adequately described by these expressions. The surface tension of nanoparticles was shown to cause a substantial increase in the O-ion conduction observed in nanoceramics. The main contribution to the conductivity was related to a region near to the particle surface.

Specific Features of Oxygen-Ionic Conduction in Oxide Nanoceramics. M.D.Glinchuk, P.I.Bykov, B.Hilczer: Physics of the Solid State, 2006, 48[11], 2199-204