Lim Taeheun, Lee Heesoo
School of Materials Science and Engineering, Pusan National University, Busan 46241, Republic of Korea.
Nanomaterials (Basel). 2025 Jun 16;15(12):934. doi: 10.3390/nano15120934.
Cobalt-based perovskite oxides exhibit remarkable catalytic activity owing to abundant oxygen vacancies and mixed ionic-electronic conductivity, but they suffer from structural instability. In contrast, iron-based perovskite oxides are thermochemically stable under oxidizing and reducing conditions but are catalytically limited. To combine these complementary properties, a composite perovskite oxide was designed and prepared by infiltrating SrCeCoO (SCC) into BaSrFeCuO (BSFC). The SCC precursor solution was dropwise applied to a BSFC|SDC|BSFC symmetric cell and heat treated. Surface morphology and compositional analyses confirmed the distribution of SCC nanoparticles on the BSFC surface. High-temperature X-ray diffraction and Rietveld refinement results revealed that both BSFC and SCC retained the cubic perovskite structure (space group Pm-3m) at room temperature. No phase transition or secondary phase formation was observed during heating from 200 to 800 °C, and the peak shifts are attributed to thermal expansion and possible oxygen loss at elevated temperatures. Upon cooling, the diffraction patterns returned to their initial state, confirming a high-temperature structural stability. XPS analysis showed an increase in the satellite peak intensity associated with Fe after SCC infiltration, and the average oxidation state of Fe decreased from 3.52 (BSFC) to 3.49 (composite perovskite oxide). The O 1s spectra revealed a higher relative content of surface-adsorbed oxygen species in the composite, indicating increased oxygen vacancy formation.
钴基钙钛矿氧化物由于具有丰富的氧空位和混合离子-电子导电性而表现出显著的催化活性，但它们存在结构不稳定性。相比之下，铁基钙钛矿氧化物在氧化和还原条件下具有热化学稳定性，但催化活性有限。为了结合这些互补特性，通过将SrCeCoO（SCC）渗透到BaSrFeCuO（BSFC）中，设计并制备了一种复合钙钛矿氧化物。将SCC前驱体溶液滴加到BSFC|SDC|BSFC对称电池上并进行热处理。表面形貌和成分分析证实了SCC纳米颗粒在BSFC表面的分布。高温X射线衍射和Rietveld精修结果表明，BSFC和SCC在室温下均保留了立方钙钛矿结构（空间群Pm-3m）。在从200℃加热到800℃的过程中，未观察到相变或二次相形成，峰位移归因于热膨胀以及高温下可能的氧损失。冷却后，衍射图谱恢复到初始状态，证实了高温结构稳定性。XPS分析表明，SCC渗透后与Fe相关的卫星峰强度增加，Fe的平均氧化态从3.52（BSFC）降至3.49（复合钙钛矿氧化物）。O 1s光谱显示复合材料中表面吸附氧物种的相对含量较高，表明氧空位形成增加。
