PMID- 27747347
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20180130
LR  - 20180130
IS  - 1463-9084 (Electronic)
IS  - 1463-9076 (Linking)
VI  - 18
IP  - 42
DP  - 2016 Oct 26
TI  - Oxygen diffusion and surface exchange in the mixed conducting oxides 
      SrTi(1-y)Fe(y)O(3-delta).
PG  - 29495-29505
AB  - Oxygen transport in the mixed ionic-electronic conducting perovskite-oxides 
      SrTi(1-y)Fe(y)O(3-delta) (with y = 0.5 and y = 1.0) was studied by oxygen isotope 
      exchange measurements. Experiments were performed on thin-film samples that were 
      grown by Pulsed Laser Deposition (PLD) on MgO substrates. Isotope penetration 
      profiles were introduced by (18)O(2)/(16)O(2) exchanges into the plane of the 
      films at various temperatures in the range 773 < T/K < 973 at an oxygen activity 
      aO(2) = 0.5. Isotope profiles were determined subsequently by Time-of-Flight 
      Secondary Ion Mass Spectrometry (ToF-SIMS), and their analysis yielded tracer 
      diffusion coefficients D* and oxygen surface exchange coefficients k*. Activation 
      energies for oxygen diffusion DeltaH(D*) and surface exchange DeltaH(k*) were obtained. 
      Isothermal values of D* and values of DeltaH(D*) are compared with literature data as 
      a function of Fe content. D* is seen to increase monotonically with Fe content; 
      DeltaH(D*) shows more complex behaviour. D* and DeltaH(D*) are also compared with the 
      predictions of defect-chemical models. Analogous comparisons with literature data 
      for k* and DeltaH(k*) indicate, in contrast to prior studies, no mechanistic 
      difference between electron-poor and electron-rich materials. It is concluded 
      that the single operative mechanism of surface exchange for the entire series of 
      STF compositions requires conduction-band electrons (minority electronic 
      charge-carriers).
FAU - Metlenko, Veronika
AU  - Metlenko V
AD  - Institute of Physical Chemistry, RWTH Aachen University, 52056 Aachen, Germany. 
      desouza@pc.rwth-aachen.de.
FAU - Jung, WooChul
AU  - Jung W
AD  - Department of Materials Science and Engineering, Massachusetts Institute of 
      Technology, Cambridge, MA 02139, USA.
FAU - Bishop, Sean R
AU  - Bishop SR
AD  - Department of Materials Science and Engineering, Massachusetts Institute of 
      Technology, Cambridge, MA 02139, USA.
FAU - Tuller, Harry L
AU  - Tuller HL
AD  - Department of Materials Science and Engineering, Massachusetts Institute of 
      Technology, Cambridge, MA 02139, USA and International Institute of Carbon 
      Neutral Energy Research, Kyushu University, Fukuoka 819-0395, Japan.
FAU - De Souza, Roger A
AU  - De Souza RA
AUID- ORCID: 0000-0001-7721-4128
AD  - Institute of Physical Chemistry, RWTH Aachen University, 52056 Aachen, Germany. 
      desouza@pc.rwth-aachen.de.
LA  - eng
PT  - Journal Article
PL  - England
TA  - Phys Chem Chem Phys
JT  - Physical chemistry chemical physics : PCCP
JID - 100888160
EDAT- 2016/10/27 06:00
MHDA- 2016/10/27 06:01
CRDT- 2016/10/18 06:00
PHST- 2016/10/27 06:00 [pubmed]
PHST- 2016/10/27 06:01 [medline]
PHST- 2016/10/18 06:00 [entrez]
AID - 10.1039/c6cp05756j [doi]
PST - ppublish
SO  - Phys Chem Chem Phys. 2016 Oct 26;18(42):29495-29505. doi: 10.1039/c6cp05756j.