1 research outputs found
Gadolinium-Doped Ceria–NaCoO<sub>2</sub> Heterogeneous Semiconductor Ionic Materials for Solid Oxide Fuel Cell Application
Solid oxide fuel cells (SOFCs) possess the merits of
high power
density, high energy conversion efficiency, and low emissions with
diverse fuels and have attracted wide attention in the energy fields.
However, the excessively high operating temperature limits its commercialization
from aspects of cost and durability. It is urgent to find other ceramic
membrane materials with superionic conductivity at low and intermediate
temperatures to reduce the temperature of SOFCs. Semiconductor ionic
composites based on oxide semiconductors can be used as heterogeneous
functional membrane materials to develop low-temperature SOFCs. Herein
we report a heterostructure material formed by gadolinium-doped ceria
(GDC) and NaCoO2 (NCO) as a functional membrane. The fuel
cell with the optimized functional composite membrane achieved a peak
power density of 1097 mW·cm–2 at 550 °C,
in which an ionic conductivity of 0.33 S·cm–1 at 550 °C was obtained for the heterostructure composite. Proton
conduction in the heterostructure composite was confirmed by X-ray
photoelectron spectroscopy, Raman spectroscopy, and electrochemical
impedance spectroscopy. Interfacial proton-transport and bulk oxygen-ion
conduction mechanisms are proposed and discussed