Efficiency of the Solid Oxide Cell (SOC) Using Nanocrystalline Mixed Ionic and Electronic Conducting (MIEC) Oxides as Air Electrode Materials in Conjunction with Doped Ceria-Based Interlayers

Abstract

AbstractNanocrystalline MIEC air electrodes, viz., La-Sr-Co-Fe and Ba-Sr-Co-Fe (6482) and nano-Gd-doped ceria (GDC) are synthesized using solution combustion technique and hydroxide co-precipitated route, respectively. Synthesized calcined nanopowders are characterized for phase purity using X-ray diffraction showing rhombohedral lattice for LSCF and cubic lattices for BSCF and GDC. Detailed transmission electron microscopy (TEM) reveals a near-net shape nanoparticles of MIEC perovskites and agglomerate free nanoparticles for GDC, and thus a composite functional layer was formulated in combination with MIEC and GDC to adhere in between electrolyte/interlayer and electrodes. Lower electrode polarizations of 0.017 Ω.cm2 and 0.17 Ω.cm2 with high exchange current density prove better electrode kinetic phenomena @850 ℃ for both LSCF-6482 and BSCF-6482 with sufficiently high current densities for both SOFC and SOEC modes of operation with the highest hydrogen generation rate of 0.62 Nl.cm−2.h−1. Cell performances are clinically correlated with the cell microstructure.