Tailoring electronic structure of perovskite cathode for proton-conducting solid oxide fuel cells with high performance

Tailoring the electronic structure of the perovskite oxide could potentially allow dramatic improvements in the properties of cathode materials in proton-conducting solid oxide fuel cells (SOFCs). This has been demonstrated in the case of Mo-doped La0.5Sr0.5FeO3-delta, where the electronic structure of the La0.5Sr0.5FeO3-delta oxide has been changed with the Mo-doping, leading to a less strong metal-oxygen bond as well as a more active surface towards oxygen reduction. As a result, the more active oxygen atoms make the formation of oxygen vacancy and hydration that are critical for protonation more feasible. Furthermore, the electric field induced by Mo-doping provides an additional driving force for the movement of protons, accelerating the proton migrations in the oxide and thus improving the cathode performance. With the Mo-doped La0.5Sr0.5FeO3-delta as the cathode, a proton-conducting SOFC exhibits an impressive fuel cell output of 1174 mW cm(-2) at 700 degrees C that surpasses most of the cells using similar types of cathodes. This study not only provides a proper cathode material without involving cobalt and barium elements but also gives an understanding of the design of the cathode by tailoring the electronic structures.

Automated summary

The study demonstrates that tailoring the electronic structure of perovskite oxide with Mo-doping leads to improvements in cathode materials for proton-conducting solid oxide fuel cells. The Mo-doping changes the electronic structure of the oxide, making the metal-oxygen bond less strong and the surface more active towards oxygen reduction, resulting in more feasible oxygen vacancy formation critical for protonation. The electric field induced by Mo-doping provides an additional driving force for proton movement, accelerating proton migration in the oxide and improving cathode performance.