Zhang Li, Xu Yangsen, Xu Kang, Chen Liyan, Zhu Feng, Liao Yuhe, Zeng Depeng, Chen Yu
School of Environment and Energy, Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, South China University of Technology, Guangzhou, 510006, China.
Small. 2025 Oct;21(42):e05019. doi: 10.1002/smll.202505019. Epub 2025 Sep 4.
Although the conventional commercial solid oxide fuel cells cathode LaSrCoFeO (LSCF) exhibits excellent electrochemical performance, its oxygen reduction reaction (ORR) kinetics are still sluggish, and Strontium (Sr) segregation is also an issue for long-term stability. Herein, a Sr-free electro-catalyst PrBaCsCoO (PBCsC) is infiltrated on the surface of LSCF to form a PBCsC-LSCF electrode, accelerating the surface oxygen exchange and thus improving the ORR activity and stability. PBCsC-LSCF shows a higher concentration of oxygen vacancies and less Sr segregation, as confirmed by the analyses of X-ray photoelectron spectroscopy (XPS). As a result, PBCsC-LSCF demonstrates an area-specific resistance of 0.010 Ω cm at 750 °C, much lower than 0.067 Ω cm of a bare LSCF. An improved peak power density of 1.70 W cm is reached from the single cell with PBCsC-LSCF at 750 °C, likely due to the higher oxygen surface exchange, as indicated by the distribution of relaxation time analyses. In addition, the cells' operational stability is greatly improved at a current density of 0.5 A cm with a degradation rate of 0.055% h, probably attributable to the suppression of Sr segregation by infiltration, as suggested by the XPS results.
尽管传统的商用固体氧化物燃料电池阴极材料镧锶钴铁氧体（LSCF）表现出优异的电化学性能，但其氧还原反应（ORR）动力学仍然迟缓，并且锶（Sr）的偏析也是影响其长期稳定性的一个问题。在此，一种无锶的电催化剂PrBaCsCoO（PBCsC）被浸润在LSCF表面，形成PBCsC-LSCF电极，加速了表面氧交换，从而提高了ORR活性和稳定性。通过X射线光电子能谱（XPS）分析证实，PBCsC-LSCF具有更高的氧空位浓度和更少的Sr偏析。结果，PBCsC-LSCF在750℃时的面积比电阻为0.010Ω·cm，远低于裸LSCF的0.067Ω·cm。在750℃下，采用PBCsC-LSCF的单电池达到了1.70W/cm的改进峰值功率密度，这可能归因于更高的氧表面交换，如弛豫时间分布分析所示。此外，在电流密度为0.5A/cm时，电池的运行稳定性得到了极大提高，降解速率为0.055%/h，这可能如XPS结果所表明的那样，是由于浸润抑制了Sr的偏析。
