title: High proton conduction in grain-boundary-free yttrium-doped barium zirconate films grown by pulsed laser deposition.
abstract: Reducing the operating temperature in the 500-750 °C range is needed for widespread use of solid oxide fuel cells (SOFCs). Proton-conducting oxides are gaining wide interest as electrolyte materials for this aim. We report the fabrication of BaZr(0.8)Y(0.2)O(3-δ) (BZY) proton-conducting electrolyte thin films by pulsed laser deposition on different single-crystalline substrates. Highly textured, epitaxially oriented BZY films were obtained on (100)-oriented MgO substrates, showing the largest proton conductivity ever reported for BZY samples, being 0.11 S cm(-1) at 500 °C. The excellent crystalline quality of BZY films allowed for the first time the experimental measurement of the large BZY bulk conductivity above 300 °C, expected in the absence of blocking grain boundaries. The measured proton conductivity is also significantly larger than the conductivity values of oxygen-ion conductors in the same temperature range, opening new potential for the development of miniaturized SOFCs for portable power supply.
authors.affiliation: NAST Center & Dipartimento di Scienze e Tecnologie Chimiche, University of Roma Tor Vergata, 00133 Rome, Italy.
authors.forename: Daniele
authors.initials: D
authors.lastname: Pergolesi
authors.forename: Emiliana
authors.initials: E
authors.lastname: Fabbri
authors.forename: Alessandra
authors.initials: A
authors.lastname: D'Epifanio
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Di Bartolomeo
authors.forename: Antonello
authors.initials: A
authors.lastname: Tebano
authors.forename: Simone
authors.initials: S
authors.lastname: Sanna
authors.forename: Silvia
authors.initials: S
authors.lastname: Licoccia
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Balestrino
authors.forename: Enrico
authors.initials: E
authors.lastname: Traversa