Innovative nanostructured and architectured oxygen electrodes for solid oxide fuel cells using electrostatic spray deposition.

International audienceIntermediate temperature solid oxide fuel cells (SOFCs) are efficient energy-conversion systems for electrical power generation. Lowering the operating temperatures (≤ 650 °C) of SOFCs are sought for decreasing the system costs and lowering material compatibility and durability issues. In order to design novel optimized cathodes with improved mixed ionic-electronic properties, it is of high importance to control (i) the electrode microstructure and composition to obtain large surface areas, increasing the number of active sites for the oxygen reduction reaction, (ii) the electrode/electrolyte interface to enhance the charge transfer. Here, we report recent results in the design of the state-of-the-art La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF) [1], La2-xPrxNiO4+δ (LPNO) [2] with 0 ≤ x ≤ 2, and Pr6O11 [3] oxygen electrodes with grain size and porosity at the nanometre length scales. These active functional layers are fabricated using electrostatic spray deposition (ESD), a unique method capable of depositing films with original morphologies by a nano-texturing approach. This talk will show our latest electrochemical performance results of these innovative oxygen electrodes investigating the role of the nanostructure and the electrode/electrolyte interface. The correlation between microstructure, composition, grain size, interfaces and electrochemical properties is discussed in detail in the different oxygen electrodes