Phase transitions of BaTi0.9Rh0.1O3±δ perovskite-type oxides under reducing environments

被引：3

作者：

Rodriguez, G. C. Mondragon ^{[1
]}

Goenuellue, Y. ^{[2
]}

Ferri, Davide ^{[3
]}

Eyssler, Arnim ^{[4
]}

Otal, Eugenio ^{[5
]}

Saruhan, B. ^{[1
]}

机构：

[1] German Aerosp Ctr DLR, Inst Mat Res, D-51147 Cologne, Germany

[2] Univ Cologne, Inst Inorgan Chem, Cologne, Germany

[3] Paul Scherrer Inst, CH-5232 Villigen, Switzerland

[4] Empa, Swiss Fed Labs Mat Sci & Technol, Lab Solid State Chem & Catalysis, CH-8600 Dubendorf, Switzerland

[5] UTN Fac Reg Santa Cruz, RA-9400 Rio Gallegos, Santa Cruz, Argentina

来源：

MATERIALS RESEARCH BULLETIN | 2015年 / 61卷

关键词：

Perovskite; Chemical synthesis; XAFS; Microstructure; SELF-REGENERATIVE FUNCTION; BARIUM TITANATE; CRYSTAL-STRUCTURE; CATALYSTS; PALLADIUM; PD; REDUCTION; OXIDATION; STATE; CO;

D O I：

10.1016/j.materresbull.2014.10.007

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Perovskite-type oxides of composition BaTi0.9Rh0.1O3 +/-delta were prepared following a new chemical route that avoids the formation of hydroxyl species and precipitation, and allows the homogeneous distribution of Rh in the final mixed metal oxide. The high dispersion of Rh and the formation of the solid solution between Rh and the BaTiO3 perovskite is confirmed by means of X-ray diffraction (XRD) and extended X-ray absorption fine structure spectroscopy (EXAFS). The presence of Rh stabilized the hexagonal BaTi0.9Rh0.1O3 +/-delta phase, which decomposes into barium orthotitanate (BaTi2O4) and metallic Rh degrees in reducing environment. This phase transition starts already at 700 degrees C and is only partially completed at 900 degrees C suggesting that part of the Rh present in the perovskite lattice might not be easily reduced by hydrogen. These aspects and further open questions are discussed. (C) 2014 Elsevier Ltd. All rights reserved.

引用

页码：130 / 135

页数：6

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