Effect of Ce Content on (La0.5Gd0.5)2(CexNbyYbyTayZry)2O7 High-entropy Oxide

ZHANG Yangyi; LIN Xiaoming; YAN Jiangrong; WANG Kerong; YANG Ying; ZHANG Yongsheng; ZHANG Dongbo

doi:10.16490/j.cnki.issn.1001-3660.2026.03.010

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Surface Technology ›› 2026, Vol. 55 ›› Issue (3) : 107-121. DOI: 10.16490/j.cnki.issn.1001-3660.2026.03.010

Special Topic—High-temperature Protective Coatings for Advanced Engines

Effect of Ce Content on (La_0.5Gd_0.5)₂(Ce_xNb_yYb_yTa_yZr_y)₂O₇ High-entropy Oxide

ZHANG Yangyi¹, LIN Xiaoming¹, YAN Jiangrong², WANG Kerong², YANG Ying¹, ZHANG Yongsheng², ZHANG Dongbo^2,*

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Abstract

High-entropy oxide ceramics have emerged as highly promising candidate materials for next-generation TBCs due to their excellent thermal properties, such as extremely low thermal conductivity and good thermal stability at high temperature. CeO₂ is used as one of the additive materials in high entropy oxides because of its excellent high temperature thermodynamic properties. It can improve the coefficient of thermal expansion and thermal conductivity of high-entropy oxides. However, the variable valence characteristics of Ce ions affect the formation of high-entropy oxides and study its effects. In this study, a new type of A₂B₂O₇ high-entropy oxide material with multiple constituent elements is synthesized by solid-phase reaction. The effects of different Ce contents and sintering temperature on high-entropy oxides are investigated by varying the content ratio of Ce in the B site in the system. X-ray diffraction is used to detect phases. Density is measured according to the Archimedes method. A scanning electron microscope is employed to observe microstructure. Energy dispersive spectroscopy is applied to identify composition. X-ray photoelectron spectroscopy is used to analyze surface of the samples. The results are as follows. An increase in the Ce ratio content leads to a decrease in the density of high-entropy oxides. The density of high-entropy oxides increases and the grain growth rate also increases with the increase of sintering temperature. Excessive high sintering temperature will lead to large grain sizes. When the atomic ratio of Ce is 0.2, the high-entropy oxides have a uniform composition distribution and high density. The optimum sintering temperature of the designed high entropy oxides is 1 550 ℃. During the sintering of Ce-doped high-entropy oxides, valence change behavior occurs, which Ce⁴⁺ is changed into Ce³⁺. This behavior occurs most drastically when sintering at 1 550 ℃, where 48.76% of Ce⁴⁺ is transformed to Ce³⁺. The Ce content in the high-entropy oxide significantly affects the density and sintering properties of high-entropy oxides. During the high-temperature sintering of high-entropy oxides, the Ce element in the high-entropy oxides undergoes valence changes.

Key words

thermal barrier coating / high-entropy oxide / phase structure / micromorphology / Ce content

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ZHANG Yangyi, LIN Xiaoming, YAN Jiangrong, WANG Kerong, YANG Ying, ZHANG Yongsheng, ZHANG Dongbo. Effect of Ce Content on (La_0.5Gd_0.5)₂(Ce_xNb_yYb_yTa_yZr_y)₂O₇ High-entropy Oxide[J]. Surface Technology. 2026, 55(3): 107-121

References

[1] LIU D R, HE W T, WEI L L, et al.Enhanced Radiative Cooling of Columnar Thermal Barrier Coatings at Ultrahigh Temperatures and Mechanisms underneath[J]. Journal of Materials Science & Technology, 2025, 239: 81-92.
[2] ZHANG Z J, JIN G, CUI X F, et al.Thermomechanical Degradation Mechanisms of High-Entropy (Yb_0.25Er_0.25Ho_0.25Y_0.25)₂SiO₅ Environmental Barrier Coatings under CMAS Melt Infiltration[J]. Journal of the European Ceramic Society, 2025, 45(15): 117606.
[3] 张晓东, 王昊, 梁逸帆, 等. 基于热障涂层的La₂Zr₂O₇材料改性研究进展[J]. 材料保护, 2024, 57(3): 50-62.
ZHANG X D, WANG H, LIANG Y F, et al.Research Progress of La₂Zr₂O₇ Material Modification Based on Thermal Barrier Coating[J]. Materials Protection, 2024, 57(3): 50-62.
[4] 王晓波, 贺智勇, 杨潇, 等. 构型熵对稀土锆酸盐陶瓷抗CaO-MgO-Al₂O₃-SiO₂侵蚀性能的影响[J]. 硅酸盐学报, 2025, 53(3): 630-639.
WANG X B, HE Z Y, YANG X, et al.Effect of Configuration Entropy on Resistance of Rare-Earth Zirconate Ceramics to CaO-MgO-Al₂O₃-SiO₂[J]. Journal of the Chinese Ceramic Society, 2025, 53(3): 630-639.
[5] MATHEW G C, THOMAS S.Novel (La_0.2Ce_0.2Pr_0.2Nd_0.2 Gd_0.2)₂Hf₂O₇ High-Entropy Pyrochlore Oxide as a Promising TBC Material[J]. Journal of the European Ceramic Society, 2025, 45(15): 117589.
[6] LU X R, YUAN J Y, LI G, et al.Preparation and Properties Evaluation of High-Entropy (La_0.2Nd_0.2Sm_0.2 Eu_0.2Gd_0.2)MgAl₁₁O₁₉ for Advanced Thermal Barrier Coating[J]. Journal of the European Ceramic Society, 2024, 44(11): 6641-6650.
[7] ROST C M, SACHET E, BORMAN T, et al.Entropy-Stabilized Oxides[J]. Nature Communications, 2015, 6: 8485.
[8] ZHAO Z F, RUAN Z Y, LI R, et al.High Entropy Pyrochlore (La_0.3Gd_0.3Ca_0.4)₂(Ti_0.2Zr_0.2Hf_0.2Nb_0.2Ta_0.2)₂O₇ Ceramic with Amorphous-Like Thermal Conductivity for Environmental/Thermal Barrier Coating Applications[J]. Journal of Materials Science & Technology, 2025, 205: 315-326.
[9] WANG J, JIN Q Q, WU P, et al.Unveiling the Mechanisms of Ultra-Low Thermal and Oxygen-Ion Conductivity in Entropy-Stabilized Ferroelastic Rare-Earth Tantalates[J]. Acta Materialia, 2025, 283: 120523.
[10] 郭磊, 孟诗钧, 叶福兴, 等. 高熵陶瓷在热障涂层与环境障涂层中的研究进展[J]. 稀有金属, 2023, 47(11): 1525-1544.
GUO L, MENG S J, YE F X, et al.Research Progress of High-Entropy Ceramic in Fields of Thermal Barrier Coatings and Environmental Barrier Coating[J]. Chinese Journal of Rare Metals, 2023, 47(11): 1525-1544.
[11] YANG L X, GENG H J, GUAN Z, et al.The Role of La and Nd in Enhancing CMAS Corrosion Resistance of High-Entropy (La,Nd,Tm,Yb,Lu)₂Zr₂O₇ Thermal Barrier Coating Materials[J]. Journal of the European Ceramic Society, 2025, 45(12): 117466.
[12] WEN W, YAN X X, PEI X H, et al.Multi-Dimensional Anisotropic Feature Interaction with Machine Learning to Predict the Thermal Conductivity of A₂B₂O₇-Type High-Entropy Ceramics[J]. Ceramics International, 2025, 51(13): 17860-17869.
[13] ZHANG J Y, ZHU J P, ZHENG J Y, et al.High Temperature Thermal Shock Resistance of Plasma-Sprayed High-Entropy (Y_0.2Yb_0.2Ho_0.2Er_0.2Tm_0.2)₂Hf₂O₇ Coating[J]. Journal of the American Ceramic Society, 2025, 108(9): e20664.
[14] LI S Y, LI C W, JIA H M, et al.Preparation and Properties of (Ce_0.2Zr_0.2Ti_0.2Sn_0.2Y_0.2-_xCa_x)O₂-_δ (x=0~0.2) High-Entropy of Compositionally-Complex Ceramics[J]. Ceramics International, 2024, 50(3): 5657-5664.
[15] GUO D H, ZHOU F F, XU B S, et al.High-Entropy (La_0.2Nd_0.2Sm_0.2Gd_0.2Yb_0.2)₂(Zr_0.75Ce_0.25)₂O₇ Thermal Barrier Coating Material with Significantly Enhanced Fracture Toughness[J]. Chinese Journal of Aeronautics, 2023, 36(4): 556-564.
[16] CHENG F H, MENG Z Q, CHENG C F, et al.Fluorite-Pyrochlore Structured High-Entropy Oxides: Tuning the Ratio of β-Site Cations for Resistance to CMAS Corrosion[J]. Corrosion Science, 2023, 218: 111199.
[17] MAO X Y, LV B W, BAO Q F, et al.Sintering Resistance and Phase Stability of (Y_0.2La_0.2Nd_0.2Sm_0.2Eu_0.2)₂Zr₂O₇ for Ultra-High Temperature Thermal Barrier Coatings[J]. Ceramics International, 2023, 49(22): 35011-35020.
[18] ZHAO S T, WANG Z H, CAO J Y, et al.Study on High-Entropy Rare-Earth Zirconate Ceramics for Thermal Barrier Coatings: High-Temperature Phase Stability, Thermophysical and Mechanical Properties[J]. Journal of Alloys and Compounds, 2025, 1010: 178047.
[19] TENG Z, ZHU L N, TAN Y Q, et al.Synthesis and Structures of High-Entropy Pyrochlore Oxides[J]. Journal of the European Ceramic Society, 2020, 40(4): 1639-1643.
[20] VAYER F, DECORSE C, BÉRARDAN D, et al. New Entropy-Stabilized Oxide with Pyrochlore Structure: Dy₂(Ti_0.2Zr_0.2Hf_0.2Ge_0.2Sn_0.2)₂O₇[J]. Journal of Alloys and Compounds, 2021, 883: 160773.
[21] 朱颖, 李勉, 芦甜, 等. (La_0.2Nd_0.2Sm_0.2Gd_0.2Y_0.2)₂Zr₂O₇一种新型高熵绝热陶瓷材料[J]. 辽宁化工, 2025, 54(3): 384-388.
ZHU Y, LI M, LU T, et al.(La_0.2Nd_0.2Sm_0.2Gd_0.2Y_0.2)₂Zr₂O₇: A Novel High-Entropy Adiabatic Ceramic Material[J]. Liaoning Chemical Industry, 2025, 54(3): 384-388.
[22] 耿浩钧, 谢芳坤, 杨凌旭, 等. (La_0.2Nd_0.2Tm_0.2Yb_0.2 Lu_0.2)₂Zr₂O₇高熵陶瓷的制备及其在熔融氧化物膜CaO-MgO-Al₂O₃-SiO₂下的腐蚀行为[J]. 中国腐蚀与防护学报, 2025, 45(5): 1244-1252.
GENG H J, XIE F K, YANG L X, et al.Preparation and Corrosion Behavior of (La_0.2Nd_0.2Tm_0.2Yb_0.2-Lu_0.2)₂Zr₂O₇ High Entropy Ceramic beneath Deposits of Molten CaO-MgO-Al₂O₃-SiO₂[J]. Journal of Chinese Society for Corrosion and Protection, 2025, 45(5): 1244-1252.
[23] ZHOU L, LI F, LIU J X, et al.High-Entropy Thermal Barrier Coating of Rare-Earth Zirconate: A Case Study on (La_0.2Nd_0.2Sm_0.2Eu_0.2Gd_0.2)₂Zr₂O₇ Prepared by Atmospheric Plasma Spraying[J]. Journal of the European Ceramic Society, 2020, 40(15): 5731-5739.
[24] WU Z T, JI W, ZHANG J Y, et al.Grain-Refining Fabrication of Nanocrystalline (La_0.2Nd_0.2Sm_0.2Gd_0.2Eu_0.2)₂Zr₂O₇ High-Entropy Ceramics by Ultra-High Pressure Sintering[J]. Journal of Materials Science & Technology, 2023, 167: 205-212.
[25] HAN Y, LIU X Y, ZHANG Q Q, et al.Ultra-Dense Dislocations Stabilized in High Entropy Oxide Ceramics[J]. Nature Communications, 2022, 13: 2871.
[26] TROFIMOV E, OSTOVARI MOGHADDAM A, LITVINYUK K, et al.Synthesis and Characterization of the RE₂A₂O₇ Oxides with an Ultrahigh-Entropy Sublattice Occupied by Rare-Earth Elements[J]. Materials Letters, 2025, 379: 137668.
[27] LUO L R, WANG W, WANG L, et al.Understanding of the Composition-Structure-Properties Relationships in High-Entropy Rare Earth Zirconates[J]. Journal of the European Ceramic Society, 2025, 45(5): 117103.
[28] ZHANG H M, ZHANG H S, CHEN X G, et al.Sm₂Gd_0.25Dy_0.25Er_0.25Yb_0.25TaO₇: A Novel Candidate Thermal Insulation Oxide for High-Temperature Coatings[J]. Ceramics International, 2024, 50(21): 44729-44735.
[29] SHUAI W W, QIAN W, GUAN Z C, et al.A Novel Dual-Phase High-Entropy (La_0.2Nd_0.2Gd_0.2Er_0.2Yb_0.2)₂Zr₂O₇ Ceramic for Thermal Barrier Coatings Applications: Preparation, Microstructure, and Thermo-Physical Properties[J]. Ceramics International, 2024, 50(7): 10525-10534.
[30] 汪宁. 新型A₂B₂O₇高熵陶瓷制备及性能的研究[D]. 北京: 华北电力大学, 2024.
WANG N.Preparation and Properties of New A₂B₂O₇ High-Entropy Ceramics[D]. Beijing: North China Electric Power University, 2024.
[31] LI Z Q, WANG Z H, MA X F, et al.High-Entropy Ceramic Dual-Phase Evolution Mechanisms and Their Influence on the Thermophysical Performance of Thermal Barrier Coatings[J]. Journal of Alloys and Compounds, 2025, 1031: 180913.
[32] LOGHMAN-ESTARKI M R, SHOJA RAZAVI R, JAMALI H, et al. Effect of Scandia Content on the Thermal Shock Behavior of SYSZ Thermal Sprayed Barrier Coatings[J]. Ceramics International, 2016, 42(9): 11118-11125.
[33] 刘晨, 刘凯旋, 刘志, 等. 氧化钇氧化铈共同稳定氧化锆陶瓷的制备与力学性能研究[J]. 陶瓷学报, 2025, 46(4): 759-766.
LIU C, LIU K X, LIU Z, et al.Preparation and Mechanical Properties of Yttria and Ceria Co-Stabilized Zirconia Ceramic Composites[J]. Journal of Ceramics, 2025, 46(4): 759-766.
[34] SHAKEEL S, SONG P, HUANG T H, et al.Insights into the Electronic, Mechanical and Thermodynamic Properties of Pyrochlore Oxides A₂B₂O₇: A First-Principles Study[J]. Journal of Physics and Chemistry of Solids, 2025, 199: 112551.
[35] 王雨豪. 抗辐照(Gd, RE)₂Zr₂O₇模拟核素陶瓷固化体设计与损伤机制[D]. 哈尔滨: 哈尔滨工业大学, 2023.
WANG Y H.Design and Damage Mechanism of Irradiation Resistant (Gd, Re)₂Zr₂O₇ Simulated Nuclide Ceramic Wasteforms[D]. Harbin: Harbin Institute of Technology, 2023.
[36] ZHONG Z Y, SONG T, ZHAO S K, et al.High-Performance BaZr_0.1Ce_0.7Y_0.1Yb_0.1O₃-_δ (BZCYYb) Protonic Ceramic Fuel Cell Electrolytes by the Ba Evaporation Inhibition Strategy[J]. Ceramics International, 2024, 50(2): 3633-3640.