Synthesis and preliminary study of pure and Zr-doped YMnO3 compounds as Solid Oxide Fuel Cells electrode

Z. MORENO; A. CANEIRO; P. ROUSSEL; G. GAUTHIER

JOURNAL OF ALLOYS AND COMPOUNDS

ELSEVIER SCIENCE SA

Lugar: Amsterdam; Año: 2017 vol. 690 p. 348 - 355

0925-8388

The Y1xZrxMnO3 series (0 x 0.30) has been studied to be used as possible SOFC electrode material. These compounds adopt a layered structure of hexagonal symmetry in which the manganese cations are located in trigonal bi-pyramidal coordination of oxygen atoms, different from that of the classical perovskite. The synthesis of the materials has been carried out by solid state reaction and X-ray diffraction technique reveals that pure phases can be obtained until x~0.10. For x ! 0.10, an additional YSZ phase is formed, similar to the SOFC electrolyte material. HT-XRD technique and thermogravimetric analysis of pure or Zr-doped YMnO3 indicate that, in diluted dry H2 for T > 600 C, these compounds are unstable, what precludes their use as anode material. On the other hand, reactivity studies at high temperature (T 1⁄4 1300 C) between Y1xZrxMnO3 (x 1⁄4 0, 0.05 and 0.1) and 8YSZ show a chemical compatibility in which the formation of an electrically insulating phase does not take place, but a crossed diffusion of Y3þ/Mn3þ and Zr4þ at the interface between both materials. Thermomechanical compati- bility in air between YSZ and Y1xZrxMnO3 is also demonstrated from RT to 850 C.