Nanoengineering of cathode layers for solid oxide fuel cells to achieve superior power densities

Solid oxide fuel cells (SOFCs) are power-generating devices with high efficiencies and considered as promising alternatives to mitigate energy and environmental issues associated with fossil fuel technologies. Nanoengineering of electrodes utilized for SOFCs has emerged as a versatile tool for significantly enhancing the electrochemical performance but needs to overcome issues for integration into practical cells suitable for widespread application. Here, we report an innovative concept for high-performance thin-film cathodes comprising nanoporous La_0.6Sr_0.4CoO_3-δ cathodes in conjunction with highly ordered, self-assembled nanocomposite La_0.6Sr_0.4Co_0.2Fe_0.8O_3-δ (lanthanum strontium cobalt ferrite) and Ce_0.9Gd_0.1O_2-δ (gadolinia-doped ceria) cathode layers prepared using pulsed laser deposition. Integration of the nanoengineered cathode layers into conventional anode-supported cells enabled the achievement of high current densities at 0.7 V reaching -2.2 and -4.7 A/cm² at 650 °C and 700 °C, respectively. This result demonstrates that tuning material properties through an effective nanoengineering approach could significantly boost the electrochemical performance of cathodes for development of next-generation SOFCs with high power output.