Jump to main content
Jump to site search
PLANNED MAINTENANCE Close the message box

Scheduled maintenance work on Wednesday 27th March 2019 from 11:00 AM to 1:00 PM (GMT).

During this time our website performance may be temporarily affected. We apologise for any inconvenience this might cause and thank you for your patience.

Issue 22, 2018
Previous Article Next Article

The blocking effect of surface dislocations on oxygen tracer diffusion in SrTiO3

Author affiliations


The existence of a polishing-induced damaged zone at the surface of standard, nominally undoped, single-crystal SrTiO3 is exploited in diffusion studies in order to investigate the interaction between oxygen vacancies and dislocations. Tracer diffusion profiles for such crystals are proposed to exhibit three features: a short feature arising from a surface space-charge layer; an intermediate, longer feature arising from the high density of dislocations in the damaged zone; and finally, a much longer feature corresponding to diffusion in the homogeneous bulk crystal. Quantitative information is provided by finite-element-method calculations. First, the distribution of oxygen vacancies in a sample in which space-charge zones depleted of oxygen vacancies form at dislocations and at the sample surface is calculated; subsequently, oxygen tracer diffusion profiles for such vacancy distributions are simulated. The proposed model is experimentally validated by performing conventional oxygen isotope exchange and depth-profiling experiments on commercial single-crystal SrTiO3. In this way, we confirm directly that arrays of dislocations in acceptor-doped SrTiO3, by virtue of the attendant space-charge tubes, hinder the diffusion of oxygen. Finally, in order to aid the prediction of oxygen tracer diffusion profiles in polished perovskite single-crystal substrates, we suggest a one-dimensional continuum approach that takes account of the complex, three-dimensional diffusion problem posed by dislocation arrays with depletion space-charge tubes.

Graphical abstract: The blocking effect of surface dislocations on oxygen tracer diffusion in SrTiO3

Back to tab navigation

Publication details

The article was received on 06 Apr 2018, accepted on 18 May 2018 and first published on 18 May 2018

Article type: Paper
DOI: 10.1039/C8CP02191K
Citation: Phys. Chem. Chem. Phys., 2018,20, 15455-15463

  •   Request permissions

    The blocking effect of surface dislocations on oxygen tracer diffusion in SrTiO3

    H. Schraknepper, T. E. Weirich and R. A. De Souza, Phys. Chem. Chem. Phys., 2018, 20, 15455
    DOI: 10.1039/C8CP02191K

Search articles by author