10.1021/am5017045.s001
Mei Li
Mei
Li
Yao Wang
Yao
Wang
Yunlong Wang
Yunlong
Wang
Fanglin Chen
Fanglin
Chen
Changrong Xia
Changrong
Xia
Bismuth
Doped Lanthanum Ferrite Perovskites as Novel
Cathodes for Intermediate-Temperature Solid Oxide Fuel Cells
American Chemical Society
2014
Bismuth Doped Lanthanum Ferrite Perovskites
Dchem
Bi doping
conductivity
novel cathode material
content
oxide fuel cells
Kchem
polarization resistance
Oxide Fuel CellsBismuth
chemical diffusion coefficient
perovskite
lanthanum strontium ferrite
oxide fuel cell cathode material
0.10 Ω cm 2
oxygen vacancy concentration
2014-07-23 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Bismuth_Doped_Lanthanum_Ferrite_Perovskites_as_Novel_Cathodes_for_Intermediate_Temperature_Solid_Oxide_Fuel_Cells/2271214
Bismuth is doped to lanthanum strontium
ferrite to produce ferrite-based
perovskites with a composition of La<sub>0.8‑x</sub>Bi<sub><i>x</i></sub>Sr<sub>0.2</sub>FeO<sub>3‑δ</sub> (0 ≤ <i>x</i> ≤ 0.8) as novel cathode material
for intermediate-temperature solid oxide fuel cells. The perovskite
properties including oxygen nonstoichiometry coefficient (δ),
average valence of Fe, sinterability, thermal expansion coefficient,
electrical conductivity (σ), oxygen chemical surface exchange
coefficient (<i>K</i><sub>chem</sub>), and chemical diffusion
coefficient (<i>D</i><sub>chem</sub>) are explored as a
function of bismuth content. While σ decreases with <i>x</i> due to the reduced Fe<sup>4+</sup> content, <i>D</i><sub>chem</sub> and <i>K</i><sub>chem</sub> increase since
the oxygen vacancy concentration is increased by Bi doping. Consequently,
the electrochemical performance is substantially improved and the
interfacial polarization resistance is reduced from 1.0 to 0.10 Ω
cm<sup>2</sup> at 700 °C with Bi doping. The perovskite with <i>x</i> = 0.4 is suggested as the most promising composition as
solid oxide fuel cell cathode material since it has demonstrated high
electrical conductivity and low interfacial polarization resistance.