Platinum Uptake and Ba₂CePtO₆ Formation During in Situ BaCe_1–xM_xO_3−δ (M = La, In) Formation

Abstract

We report the formation, structures, temperature-dependent phase transitions, and high-temperature reactivity of the potential proton and oxide ion conductors BaCe(1-x)M(x)O3 (M(3+) = In(3+), La(3+)). The present in situ diffraction studies show oxidative platinum uptake at temperatures as low as 950 °C into BaCeO3, forming the cubic Ba2CePtO6 double perovskite. The transient B-site double perovskite expels platinum at around 1200-1250 °C. Platinum oxidation via BaCeO3 is investigated by in situ powder X-ray and neutron diffraction experiments in various atmospheres. Doped BaCe(1-x)M(x)O3 phases show the formation of Ba2CePtO6 without incorporating the M(3+) dopant. Oxidative platinum uptake is also observed during the synthesis of BaCeO3 on platinum metal. We report the reaction pathway for the low-temperature oxidative formation of Ba2CePtO6 and the subsequent liberation of platinum for the barium cerate system. The findings are supported by ambient-temperature X-ray diffraction, in situ powder X-ray, and powder neutron diffraction as well as XPS.

A Novel Platinum Modified Barium Zirconate-Based Electrolyte for Enhanced Solid Oxide Fuel Cell Performance

“…Bi has recently provided a definitive result regarding the diffusion of Pt into the lattice of BZY [16]. Another study indicates that at elevated temperatures, Pt has the potential to undergo a reaction with BaCeO3, resulting in the formation of different proton conductor phases [17]. It follows that Pt is not totally inert with proton-conducting oxides, and that a reaction will take place between Pt and BZY.…”

Fabrication of (110)-one-axis-oriented perovskite-type oxide thin films and their application to buffer layer

“…12) Another candidate electrolyte of IT-SOFCs is doped SrZrO 3 because it shows excellent chemical stability in the intermediate temperature range. 13) The crystal structure of BaCe 1−x Y x O 3−δ has been studied by a number of investigators, [14][15][16][17][18] and the crystal structure and phase of BaCe 1−x Y x O 3−δ that depend on the Y concentration, appeared to be orthorhombic for x ≤ 0.1 and rhombohedral for x ≥ 0.15. In this study, we adopted BaCe 0.9 Y 0.1 O 3−δ (BCYO) as a target material and our BCYO thin film has an orthorhombic crystal structure.…”