posted on 2024-01-24, 14:13authored byFeng Zhu, Kang Xu, Fan He, Yangsen Xu, Zhiwei Du, Hua Zhang, Depeng Zeng, Ying Liu, Haobing Wang, Dong Ding, Yucun Zhou, Yu Chen
Intermediate-temperature ceramic fuel cells are attractive
for
clean and efficient energy conversion. Their commercialization, however,
is primarily impeded by insufficient electrode electrocatalytic activity
for the oxygen reduction reaction (ORR) and poor tolerance against
contaminants. Here we report our design of a layered high-entropy
electrode, Pr0.2Sm0.2Nd0.2Gd0.2La0.2BaCo2O5+δ (PSNGLBC), for fast and durable ORR. When it is used as an electrode
on ceramic fuel cells, a low area-specific resistance of 0.010 Ω
cm2 and an impressive maximum power density of 2.03 W cm–2 are achieved at 800 °C. When Cr contamination
is introduced, the high-entropy PSNGLBC electrode shows a dramatically
enhanced durability compared to the PrBaCo2O5+δ electrode. The improved ORR activity and stability and contaminants
tolerance of the PSNGLBC electrode may be attributed to the synergistic
enhancement of entropy-dominated stabilization effect and lattice
distortion, significantly enhancing the electrocatalytic activity
and promoting the formation of a stable crystal morphology and phase
structure.