Self-assembled Fe-doped PrBaCo2O5+δ composite cathodes with disorder transition region for intermediate-temperature solid oxide fuel cells
Min Fu, Xin Lin, Lingui Tan, Ping Zhang, Haijiao Xie, Zetian Tao
Abstract
PrBa(Co 1-x Fe x ) 2 O 5+δ polymorphs (0.1 < x < 0.4, denoted as PBCF-x with Fe-doping level x) are reported and dual phase of cubic phase Pr 0.5 Ba 0.5 Co 1−x Fe x O 3−δ and tetragonal phase PrBa(Co 1-x Fe x ) 2 O 5+δ are co-produced through an common sol–gel method. The co-generation of the dual-phases leads to the formation of abundant hetero-interfaces between the neighboring crystal phases and the synergic effect demonstrates remarkably high oxygen adsorption and dissociation ability in the air. The density functional theory (DFT) calculation establishes that the existence of hetero-interfaces promotes oxygen reduction reaction activity (ORR) which is crucial to improve cathode performance of proton-conducing solid oxide fuel cells (H–SOFCs). Moreover, an outstanding electrochemical performance is obtained for the single cell with a PBCF03 cathode and the research demonstrates that a self-assemble dual phase cathode can be an effective approach for developing high-performing H–SOFCs.