In the rapidly evolving aerospace sector, the quest for sophisticated thermal barrier coating (TBC) materials has intensified. These materials are primarily sought for their superior comprehensive thermal characteristics, which include a low thermal conductivity coupled with a high coefficient of thermal expansion (CTE) that synergizes with the substrate. In our study, we adopt a solid-state method to synthesize a series of high-entropy rare-earth cerates: La₂Ce₂O₇ (1RC), (La_1/2Nd_1/2)₂Ce₂O₇ (2RC), (La_1/3Nd_1/3Sm_1/3)₂Ce₂O₇ (3RC), (La_1/4Nd_1/4Sm_1/4Eu_1/4)₂Ce₂O₇ (4RC), and (La_1/5Nd_1/5Sm_1/5Eu_1/5Gd_1/5)₂Ce₂O₇ (5RC), all sintered at 1600 °C for 10 h. We thoroughly examine their phase structure, morphology, elemental distribution, and thermal properties. Our in-depth analysis of the phonon scattering mechanisms reveals that 4RC and 5RC exhibit exceptional thermal properties: high CTEs of 13.00 × 10⁻⁶ K⁻¹ and 12.77 × 10⁻⁶ K⁻¹ at 1400 °C, and low thermal conductivities of 1.55 W/(m·K) and 1.68 W/(m·K) at 1000 °C, respectively. Compared to other TBC systems, 4RC and 5RC stand out for their excellent thermal characteristics. This study significantly contributes to the development of high-entropy oxides for TBC applications.

在快速发展的航空航天领域，对复杂热障涂层 (TBC) 材料的需求不断加剧。这些材料主要因其卓越的综合热特性而受到青睐，其中包括低热导率以及与基材协同作用的高热膨胀系数 (CTE)。在我们的研究中，我们采用固相法合成了一系列高熵稀土铈酸盐：La ₂ Ce ₂ O ₇ (1RC)、(La _1/2 Nd _1/2 ) ₂ Ce ₂ O ₇ ( 2RC)、(La _1/3 Nd _1/3 Sm _1/3 ) ₂ Ce ₂ O ₇ (3RC)、(La _1/4 Nd _1/4 Sm _1/4 Eu _1/4 ) ₂ Ce ₂ O ₇ ( 4RC)和(La _1/5 Nd _1/5 Sm _1/5 Eu _1/5 Gd _1/5 ) ₂ Ce ₂ O ₇ (5RC)，均在1600℃下烧结10小时。我们彻底检查了它们的相结构、形态、元素分布和热性能。我们对声子散射机制的深入分析表明，4RC 和 5RC 表现出优异的热性能：1400 °C 时的高 CTE 为 13.00 × 10 ^-6  K ^-1和 12.77 × 10 ^-6  K ^-1  ，以及低热导率1000 °C 时分别为 1.55 W/(m·K) 和 1.68 W/(m·K)。与其他 TBC 系统相比，4RC 和 5RC 因其出色的热特性而脱颖而出。这项研究对 TBC 应用高熵氧化物的开发做出了重大贡献。