Effect of phosphorus additions on the sintering and transport properties of proton conducting BaZr(0.85)Y(0.15)O3-delta

authors	Soares, HS; Zhang, X; Antunes, I; Frade, JR; Mather, GC; Fagg, DP
nationality	International
journal	JOURNAL OF SOLID STATE CHEMISTRY
author keywords	BZY; Ceramic proton conductor; Dispersants; Sintering aids; Phosphate esters; Barium zirconate
keywords	DOPED BARIUM ZIRCONATE; OXIDE FUEL-CELLS; PHOSPHATE ESTER; THIN-FILMS; BATIO3; ELECTROLYTE; MICROSTRUCTURE; DISPERSION; CERAMICS; TITANATE
abstract	The influence of phosphorous additions on the sintering and electrical transport properties of the proton-conducting perovskite BaZr0.85Y0.15O3-delta (BZY) has been studied with a view to the use of phosphates as typical dispersants for the formation of stabilised solid suspensions or as possible sintering aids. P2O5 additions, (1-x)BZY.xP(2)O(5), monotonously promote densification in the intermediate compositional range 0.04 <= x <= 0.08. Nonetheless, BZY reacts with phosphorous forming the phase Ba-3(PO4)(2) at temperatures as low as 600 degrees C. The associated loss of Ba from the perovskite, leads to a decrease in the perovskite lattice parameter, the formation of yttria-based impurity phases and impaired grain growth. Such reaction has an extremely detrimental effect on bulk and grain boundary conductivities. It is, therefore, vital that the current results are taken into account by the protonics community when attempting to prepare the stabilised solid suspensions of BZY nanopowders required for thin ceramic applications. Alternative dispersants to phosphate esters must be found. (C) 2012 Elsevier Inc. All rights reserved.
publisher	ACADEMIC PRESS INC ELSEVIER SCIENCE
issn	0022-4596
year published	2012
volume	191
beginning page	27
ending page	32
digital object identifier (doi)	10.1016/j.jssc.2012.02.053
web of science category	Chemistry, Inorganic & Nuclear; Chemistry, Physical
subject category	Chemistry
unique article identifier	WOS:000305670700005