Open AccessCOMPUTATIONAL MODELING, SYNTHESIS, AND CHARACTERIZATION OF BaZr1-xYxO3-8 SOLID STATE PROTON CONDUCTOR
Author(s) -
Boris V. Merinov,
C. O. Dorso,
William A. Goddard,
Jian Wu,
Sossina M. Haile
Publication year - 2003
Language(s) - English
Resource type - Reports
DOI - 10.2172/833847
Subject(s) - analytical chemistry (journal) , crystallography , proton conductor , conductivity , proton , materials science , perovskite (structure) , crystallite , chemistry , chromatography , quantum mechanics , physics , electrode , electrolyte
During the second semiannual period we have carried out a series of QM calculations on the BaZr{sub 1-x}Y{sub x}H{sub x}O{sub 3} proton conductor to determine the equilibrium proton positions and corresponding energies. We find that the size of the crystal cell is very important for the identification of the equilibrium proton positions. To derive ReaxFF parameters for Pt-surfaces and for H-transfer in Y-doped BaZrO{sub 3}, we carried out QM-calculations on the structures and energies of relevant condensed phases and cluster systems. These data then served as a training set to optimize the ReaxFF parameters. ReaxFF for various bulk metals (Pt, Zr, and Y) and metal clusters (Pt) was developed. BaZr{sub 1-x}Y{sub x}O{sub 3-{delta}} with x = 0.2, 0.3, 0.4, 0.5 was synthesized using a modified Pechini method and characterization (X-ray diffraction, scanning electron microscopy, and impedance spectroscopy) of this material was performed. We find that a single perovskite phase is formed in BaZr{sub 1-x}Y{sub x}O{sub 3-{delta}}. The proton conductivity of BaZr{sub 1-x}Y{sub x}O{sub 3-{delta}} with x = 0.5 is significantly lower than the conductivity of the samples with Y-dopant concentrations of 0.1 and 0.2