TY  - JOUR
AU  - Sadykov, S.
AU  - , Okhupin. Yu.
AU  - Yeremeev, N.
AU  - Vinokurov, Z.
AU  - Shmakov, A.
AU  - Belyaev, V.
AU  - Uvarov, N.
AU  - Mertens, Josef
TI  - In situ X-ray diffraction studies of Pr2 − xNiO4 + δ crystal structure  relaxation caused by oxygen loss
JO  - Solid state ionics
VL  - 13292
SN  - 1872-7689
CY  - Amsterdam [u.a.]
PB  - Elsevier Science
M1  - FZJ-2014-01378
SP  - 5
PY  - 2014
AB  - Fine powders of Pr2 − xNiO4 + δ (PNO) oxides (x=0÷0.3) synthesized by Pechini routewere uniaxially pressedinto pellets and sintered at 1300 °C under air. Chemical diffusion coefficients (Dchem.) and surface exchange constants(kchem.) were estimated by analysis of the weight and conductivity relaxations after step-wise change ofpO2. In situ XRD studies were carried out in VEPP-3 facilities of the Siberian Center of Synchrotron Radiationusing unique high-temperature camera and procedures.Analysis of dynamics of the cell volume expansion caused by oxygen loss with due regard for penetration depthof X-rays into the pellet allowed to estimate Dchem and kchem found to be close to those obtained by traditionalmethods. Isolated Pr vacancies appear to be the most important for fast oxygen diffusion and high surface reactivityproviding the highest values of kchem and Dchem for Pr1.9NiO4 + δ composition.
Y2  - 1 Feb 2014
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000338810500201
DO  - DOI:10.1016/j.ssi.2014.02.001
UR  - https://juser.fz-juelich.de/record/151425
ER  -