Structure and electrochemical properties of titanate perovskite with in situ exsolution as a ceramic electrode material

In this work, the structure and electrochemical properties of titanate ceramics with in situ Ni exsolution are investigated to identify the structure-performance relationship of the exsolved perovskite for use as electrode materials in solid oxide cells. The phase formation, redox behaviour and exsolution properties of the material have been studied. The characteristics of the individual electrochemical processes are identified and correlated with the Ni doping and microstructural evolution. The results indicate that the electrode activity is strongly dependent on the density and particle size of the in situ grown Ni nanoparticles. The interfacial ion transfer and charge transfer processes can be promoted by increasing the electrode surface area or improving the adhesion between the electrode and electrolyte, while the surface electrode processes including the dissociative adsorption are more dependent on the porosity and electrode/electrolyte interfacial region of the exsolved titanate electrode.