A dual modification strategy of highly active catalytic cathode for proton-conducting solid oxide fuel cell with Ni-doped PrBaFe_1.9Mo_0.1O_6-δ

The cathode catalytic activity and stability in a temperature range of 550–700 °C is crucial to the development of proton-conductive solid oxide fuel cells (PCFCs). A facile dual-modification strategy is developed for the design of Ni-doped PrBaFe_1.9Mo_0.1O_6-δ (PBFMN), composed of a major perovskite and a minor NiO phases, as a cobalt-free cathode. The composite cathode PBFMN exhibits high catalytic activity and stability. Computational simulation indicates that the perovskite phase increases the oxygen vacancies and enhances the proton transfer, while nickel oxide nanoparticles improve oxygen adsorption and dissociation. The fuel cell with as-prepared PBFMN reached a peak power density 1.23 W cm⁻² at 700 °C. The improved performance of the cell is mainly due to the fast ORR kinetics. This work provides a new insight into the design of cobalt-free cathode for a PCFC.