Details

Autor(en) / Beteiligte

• Berti, G
• Sanna, S
• Castellano, C
• Van Duijn, J
• Ruiz-Bustos, R
• Bordonali, L
• Bussetti, G
• Calloni, A
• Demartin, F
• Duò, L
• Brambilla, A

Titel

Observation of Mixed Valence Ru Components in Zn Doped Y2Ru2O7 Pyrochlores

Ist Teil von

• Journal of physical chemistry. C, 2016-06, Vol.120 (22), p.11763-11768

Ort / Verlag

American Chemical Society

Erscheinungsjahr

2016

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• We present a study of Y2–x Zn x Ru2O7 pyrochlores as a function of the Zn doping level x. X-ray diffraction measurements show that single-phase samples could be obtained for x < 0.2. Within the allowed range for x, dc conductivity measurements revealed a sizable decrease in resistivity at all the investigated temperatures for Zn doped samples with respect to undoped ones. Neutron diffraction data of the x = 0.2 sample showed that replacing Y3+ by Zn2+ does not result in the formation of oxygen vacancies. X-ray photoemission spectroscopy measurements revealed that part of the Ru ions are in the 5+ oxidation state to balance, in terms of electronic charge, the incorporation of Zn2+. The results give experimental evidence that the heterovalent doping promotes the increase of conductivity in the Y2Ru2O7 pyrochlores, making these systems promising as intermediate-temperature solid oxide fuel cell cathodes.