Nb and Cu co-doped (La,Sr)(Co,Fe)O3: a stable electrode for solid oxide cells.

D M Neacsa,P L Coddet,K Abbassi,M El Amrani,V Ta Phuoc,S Dealmeida-Didry,H Guesmi,S Roger,C Autret-Lambert,R Sopracase,J Vulliet,F Gervais

doi:10.1039/d0ra10313f

Abstract

Solid oxide cells (SOCs) are electrochemical devices that convert the chemical energy of a fuel into electricity. With regard to electrodes, the development of materials with mixed conduction properties is a key issue for improving the performance of SOCs at high temperatures. New Cu and Nb co-doping La1−xSrxFeyCo1−yO3−δ (LSCF) materials were studied as electrode materials on yttria-stabilized zirconia (YSZ) supports. The results show that Cu0.05 + Nb0.05 co-doped LSCF maintains a stable cubic structure even after several heat treatments and has better conductivity than a classically used LSCF.

Highlights

Solid oxide cells (SOCs) appear to be a promising technology for the reversible conversion of gas to electricity.[1]
In mixed ionic and electronic conductors (MIEC), the reaction can extend from the vicinity of triple phase boundaries (TPBs) to the whole surface area of the porous electrode, resulting in a substantial increase in performance
The pure and doped LSCF samples were deposited by screen-printing on symmetrical cells (YSZ electrolyte covered by a 4 mm thick GDC barrier layer on both faces) to be tested

Summary

Introduction

Solid oxide cells (SOCs) appear to be a promising technology for the reversible conversion of gas to electricity.[1] They are electrochemical devices that can reach high conversion efficiencies due to their high operating temperatures (800–1000 C). Hydrogen is used as a fuel and pure oxygen or oxygen air is used as an oxidizer. To increase their efficiency, particular attention must be paid to the development of electrode materials. LSCF material crystallizes in an ABO3 perovskite structure in which A-sites are occupied by large La and Sr cations and B-sites are preferably lled by smaller Co and Fe cations. Different crystallized phases can be found for LSCF depending on the synthesis method and sintering temperature, such as an orthorhombic, rhombohedral or cubic structure.[3,4]

Results

Discussion

Conclusion