%0 Journal Article
%A Wahyudi, O.
%A Ceretti, M.
%A Weill, I.
%A Cousson, A.
%A Weill, F.
%A Meven, M.
%A Guerre, M.
%A Villesuzanne, A.
%A Bassat, J.-M.
%A Paulus, W.
%T Growth of high quality single crystals of strontium doped (Nd,Pr)-nickelates, Nd $_{2−x}$ Sr $_{x}$ NiO $_{4+δ}$ and Pr $_{2−x}$ Sr $_{x}$ NiO $_{4+δ}$
%J CrystEngComm
%V 17
%N 33
%@ 1466-8033
%C London
%I RSC
%M FZJ-2016-01634
%P 6278 - 6285
%D 2015
%X Large size and high quality single crystals of Nd2−xSrxNiO4+δ and Pr2−xSrxNiO4+δ, with selected composition (x = 0.0, 0.1 and 0.5), were grown by a floating-zone technique using an image furnace. We found that even small deviations from the ideal cation stoichiometry led to either NiO segregation or formation of Ni-poor Pr4Ni3O10−x, or RExOy intergrowth phases, rendering the title compounds unstable even under ambient conditions. Related to potential applications as membranes in SOFC, we importantly found Nd2−xSrxNiO4+δ and Pr2−xSrxNiO4+δ powders, obtained from ground stoichiometric single crystals, to be stable in air at high temperature (1000 °C), contrary to the partial decomposition observed when synthesized as polycrystalline powders by classical solid state synthesis. The presence of NiO/Pr4Ni3O10−x or RExOy intergrowth phases are discussed as a drawback limiting high temperature stability for Pr2NiO4+δ. Grown single crystals were characterised by neutron and X-ray diffraction as well as by electron microscopy (SEM/EDS), revealing their excellent quality in terms of composition, homogeneity and crystallinity. For each crystal, the oxygen content was determined by thermogravimetric analysis in a reductive atmosphere. Transmission electron microscopy highlighted a complex incommensurate structure for Pr2NiO4.25 and Nd2NiO4.25 with a 2D modulation vector related to oxygen ordering.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000359270700004
%R 10.1039/C5CE00906E
%U https://juser.fz-juelich.de/record/282889