AI Chat Paper
Note: Please note that the following content is generated by AMiner AI. SciOpen does not take any responsibility related to this content.
{{lang === 'zh_CN' ? '文章概述' : 'Summary'}}
{{lang === 'en_US' ? '中' : 'Eng'}}
Chat more with AI
PDF (4.4 MB)
Submit Manuscript AI Chat Paper
Show Outline
Show full outline
Hide outline
Show full outline
Hide outline
Research Article | Open Access

High-entropy (La0.2Nd0.2Sm0.2Eu0.2Gd0.2)2Ce2O7: A potential thermal barrier material with improved thermo-physical properties

Yun XUEa,bXiaoqin ZHAOa,bYulong ANa,b( )Yijing WANGa,bMeizhen GAOcHuidi ZHOUa,bJianmin CHENa,b
Key Laboratory of Science and Technology on Wear and Protection of Materials, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China
Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
Key Lab for Magnetism and Magnetic Materials of MOE, School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China
Show Author Information

Graphical Abstract


High-entropy oxides (HEOs) are widely researched as potential materials for thermal barrier coatings (TBCs). However, the relatively low thermal expansion coefficient (TEC) of those materials severely restricts their practical application. In order to improve the poor thermal expansion property and further reduce the thermal conductivity, high-entropy (La0.2Nd0.2Sm0.2Eu0.2Gd0.2)2Ce2O7 is designed and synthesized in this work. The as-prepared multicomponent material is formed in a simple disordered fluorite structure due to the high-entropy stabilization effect. Notably, it exhibits a much higher TEC of approximately 12.0 × 10-6 K-1 compared with those of other high-entropy oxides reported in the field of TBCs. Besides, it presents prominent thermal insulation behavior with a low intrinsic thermal conductivity of 0.92 W·m-1·K-1 at 1400 ℃, which can be explained by the existence of high concentration oxygen vacancies and highly disordered arrangement of multicomponent cations in the unique high-entropy configuration. Through high-temperature in-situ X-ray diffraction (XRD) measurement, this material shows excellent phase stability up to 1400 ℃. Benefiting from the solid solution strengthening effect, it shows a higher hardness of 8.72 GPa than the corresponding single component compounds. The superior thermo-physical performance above enables (La0.2Nd0.2Sm0.2Eu0.2Gd0.2)2Ce2O7 a promising TBC material.


Rost CM, Sachet E, Borman T, et al. Entropy-stabilized oxides. Nat Commun 2015, 6: 8485.
Sarker P, Harrington T, Toher C, et al. High-entropy high-hardness metal carbides discovered by entropy descriptors. Nat Commun 2018, 9: 4980.
Harrington TJ, Gild J, Sarker P, et al. Phase stability and mechanical properties of novel high entropy transition metal carbides. Acta Mater 2019, 166: 271-280.
Rost CM, Borman T, Hossain MD, et al. Electron and phonon thermal conductivity in high entropy carbides with variable carbon content. Acta Mater 2020, 196: 231-239.
Jin T, Sang XH, Unocic RR, et al. Mechanochemical- assisted synthesis of high-entropy metal nitride via a soft urea strategy. Adv Mater 2018, 30: 1707512.
Gild J, Zhang YY, Harrington T, et al. High-entropy metal diborides: A new class of high-entropy materials and a new type of ultrahigh temperature ceramics. Sci Rep 2016, 6: 37946.
Feng L, Fahrenholtz WG, Hilmas GE. Processing of dense high-entropy boride ceramics. J Eur Ceram Soc 2020, 40: 3815-3823.
Zhang RZ, Gucci F, Zhu H, et al. Data-driven design of ecofriendly thermoelectric high-entropy sulfides. Inorg Chem 2018, 57: 13027-13033.
Qin Y, Liu JX, Li F, et al. A high entropy silicide by reactive spark plasma sintering. J Adv Ceram 2019, 8: 148-152.
Qin Y, Wang JC, Liu JX, et al. High-entropy silicide ceramics developed from (TiZrNbMoW)Si2 formulation doped with aluminum. J Eur Ceram Soc 2020, 40: 2752-2759.
Xiang HM, Xing Y, Dai FZ, et al. High-entropy ceramics: Present status, challenges, and a look forward. J Adv Ceram 2021, 10: 385-441.
Wang QS, Sarkar A, Wang D, et al. Multi-anionic and -cationic compounds: New high entropy materials for advanced Li-ion batteries. Energy Environ Sci 2019, 12: 2433-2442.
Ghigna P, Airoldi L, Fracchia M, et al. Lithiation mechanism in high-entropy oxides as anode materials for Li-ion batteries: An operando XAS study. ACS Appl Mater Interfaces 2020, 12: 50344-50354.
Lun ZY, Ouyang B, Kwon DH, et al. Cation-disordered rocksalt-type high-entropy cathodes for Li-ion batteries. Nat Mater 2021, 20: 214-221.
Jiang B, Yu Y, Cui J, et al. High-entropy-stabilized chalcogenides with high thermoelectric performance. Science 2021, 371: 830-834.
Chen H, Xiang HM, Dai FZ, et al. High entropy (Yb0.25Y0.25Lu0.25Er0.25)2SiO5 with strong anisotropy in thermal expansion. J Mater Sci Technol 2020, 36: 134-139.
Zhao ZF, Chen H, Xiang HM, et al. High entropy defective fluorite structured rare-earth niobates and tantalates for thermal barrier applications. J Adv Ceram 2020, 9: 303-311.
Ren K, Wang QK, Shao G, et al. Multicomponent high- entropy zirconates with comprehensive properties for advanced thermal barrier coating. Scripta Mater 2020, 178: 382-386.
Lashmi PG, Ananthapadmanabhan PV, Unnikrishnan G, et al. Present status and future prospects of plasma sprayed multilayered thermal barrier coating systems. J Eur Ceram Soc 2020, 40: 2731-2745.
Zhao M, Ren XR, Yang J, et al. Thermo-mechanical properties of ThO2-doped Y2O3 stabilized ZrO2 for thermal barrier coatings. Ceram Int 2016, 42: 501-508.
Cao XQ, Vassen R, Tietz F, et al. New double-ceramic- layer thermal barrier coatings based on zirconia-rare earth composite oxides. J Eur Ceram Soc 2006, 26: 247-251.
Dwivedi G, Viswanathan V, Sampath S, et al. Fracture toughness of plasma-sprayed thermal barrier ceramics: Influence of processing, microstructure, and thermal aging. J Am Ceram Soc 2014, 97: 2736-2744.
Ren XR, Pan W. Mechanical properties of high-temperature- degraded yttria-stabilized zirconia. Acta Mater 2014, 69: 397-406.
Xing C, Yi MY, Shan X, et al. Sintering behavior of a nanostructured thermal barrier coating deposited using electro-sprayed particles. J Am Ceram Soc 2020, 103: 7267-7282.
Limarga AM, Shian S, Baram M, et al. Effect of high- temperature aging on the thermal conductivity of nanocrystalline tetragonal yttria-stabilized zirconia. Acta Mater 2012, 60: 5417-5424.
Tan Y, Longtin JP, Sampath S, et al. Effect of the starting microstructure on the thermal properties of as-sprayed and thermally exposed plasma-sprayed YSZ coatings. J Am Ceram Soc 2009, 92: 710-716.
Wang YX, Zhou CG. Hot corrosion behavior of nanostructured Gd2O3 doped YSZ thermal barrier coating in presence of Na2SO4 + V2O5 molten salts. Prog Nat Sci Mater Int 2017, 27: 507-513.
Wei QL, Guo HB, Gong SK. Microstructure evolution of Nd2O3 and Yb2O3 co-doped YSZ thermal barrier coatings during high temperature exposure. Mater Sci Forum 2007, 546-549: 1735-1738.
Wang Q, Guo L, Yan Z, et al. Phase composition, thermal conductivity, and toughness of TiO2-doped, Er2O3-stabilized ZrO2 for thermal barrier coating applications. Coatings 2018, 8: 253.
Cao XQ, Vassen R, Fischer W, et al. Lanthanum-cerium oxide as a thermal barrier-coating material for high- temperature applications. Adv Mater 2003, 15: 1438-1442.
Shen ZY, Liu GX, Mu RD, et al. Effects of Er stabilization on thermal property and failure behavior of Gd2Zr2O7 thermal barrier coatings. Corros Sci 2021, 185: 109418.
Wang J, Chong XY, Zhou R, et al. Microstructure and thermal properties of RETaO4 (RE = Nd, Eu, Gd, Dy, Er, Yb, Lu) as promising thermal barrier coating materials. Scripta Mater 2017, 126: 24-28.
Wang CJ, Wang Y. Thermophysical properties of La2(Zr0.7Ce0.3)2O7 prepared by hydrothermal synthesis for nano-sized thermal barrier coatings. Ceram Int 2015, 41: 4601-4607.
Zhang RZ, Reece MJ. Review of high entropy ceramics: Design, synthesis, structure and properties. J Mater Chem A 2019, 7: 22148-22162.
Braun JL, Rost CM, Lim M, et al. Charge-induced disorder controls the thermal conductivity of entropy-stabilized oxides. Adv Mater 2018, 30: 1805004.
Wright AJ, Wang QY, Ko ST, et al. Size disorder as a descriptor for predicting reduced thermal conductivity in medium-and high-entropy pyrochlore oxides. Scripta Mater 2020, 181: 76-81.
Zhao ZF, Xiang HM, Dai FZ, et al. (La0.2Ce0.2Nd0.2Sm0.2Eu0.2)2Zr2O7: A novel high-entropy ceramic with low thermal conductivity and sluggish grain growth rate. J Mater Sci Technol 2019, 35: 2647-2651.
Chen H, Zhao ZF, Xiang HM, et al. High entropy (Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12: A novel high temperature stable thermal barrier material. J Mater Sci Technol 2020, 48: 57-62.
Ren K, Wang QK, Cao YJ, et al. Multicomponent rare- earth cerate and zirconocerate ceramics for thermal barrier coating materials. J Eur Ceram Soc 2021, 41: 1720-1725.
Schlichting KW, Padture NP, Klemens PG. Thermal conductivity of dense and porous yttria-stabilized zirconia. J Mater Sci 2001, 36: 3003-3010.
Che JW, Wang XZ, Liu XY, et al. Thermal transport property in pyrochlore-type and fluorite-type A2B2O7 oxides by molecular dynamics simulation. Int J Heat Mass Transf 2022, 182: 122038.
Yamamura H, Nishino H, Kakinuma K, et al. Crystal phase and electrical conductivity in the pyrochlore-type composition systems, Ln2Ce2O7 (Ln = La, Nd, Sm, Eu, Gd, Y and Yb). J Ceram Soc Jpn 2003, 111: 902-906.
Shannon RD. Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides. Acta Crystallogr Sect A 1976, 32: 751-767.
Teng Z, Tan YQ, Zeng SF, et al. Preparation and phase evolution of high-entropy oxides A2B2O7 with multiple elements at A and B sites. J Eur Ceram Soc 2021, 41: 3614-3620.
Zhang YL, Guo L, Yang YP, et al. Influence of Gd2O3 and Yb2O3 co-doping on phase stability, thermo-physical properties and sintering of 8YSZ. Chin J Aeronaut 2012, 25: 948-953.
Feng J, Xiao B, Zhou R, et al. Thermal expansion and conductivity of RE2Sn2O7 (RE = La, Nd, Sm, Gd, Er and Yb) pyrochlores. Scripta Mater 2013, 69: 401-404.
Zhang HS, Wei Y, Li G, et al. Investigation about thermal conductivities of La2Ce2O7 doped with calcium or magnesium for thermal barrier coatings. J Alloys Compd 2012, 537: 141-146.
Zhong XH, Xu ZH, Zhang YF, et al. Phase stability and thermophysical properties of neodymium cerium composite oxide. J Alloys Compd 2009, 469: 82-88.
Zhang HS, Zhao LM, Sang WW, et al. Thermophysical performances of (La1/6Nd1/6Yb1/6Y1/6Sm1/6Lu1/6)2Ce2O7 high- entropy ceramics for thermal barrier coating applications. Ceram Int 2022, 48: 1512-1521.
Zhang HS, Liao SR, Dang XD, et al. Preparation and thermal conductivities of Gd2Ce2O7 and (Gd0.9Ca0.1)2Ce2O6.9 ceramics for thermal barrier coatings. J Alloys Compd 2011, 509: 1226-1230.
Clarke DR. Materials selection guidelines for low thermal conductivity thermal barrier coatings. Surf Coat Technol 2003, 163-164: 67-74.
Klemens PG. The scattering of low-frequency lattice waves by static imperfections. Proc Phys Soc A 1955, 68: 1113-1128.
Callaway J, von Baeyer HC. Effect of point imperfections on lattice thermal conductivity. Phys Rev 1960, 120: 1149-1154.
Tian ZL, Lin CF, Zheng LY, et al. Defect-mediated multiple-enhancement of phonon scattering and decrement of thermal conductivity in (YxYb1-x)2SiO5 solid solution. Acta Mater 2018, 144: 292-304.
Chen L, Hu MY, Wu P, et al. Thermal expansion performance and intrinsic lattice thermal conductivity of ferroelastic RETaO4 ceramics. J Am Ceram Soc 2019, 102: 4809-4821.
Chen L, Jiang YH, Chong XY, et al. Synthesis and thermophysical properties of RETa3O9 (RE = Ce, Nd, Sm, Eu, Gd, Dy, Er) as promising thermal barrier coatings. J Am Ceram Soc 2018, 101: 1266-1278.
Wu FS, Wu P, Zhou YX, et al. The thermo-mechanical properties and ferroelastic phase transition of RENbO4 (RE = Y, La, Nd, Sm, Gd, Dy, Yb) ceramics. J Am Ceram Soc 2020, 103: 2727-2740.
Chen L, Wu P, Song P, et al. Potential thermal barrier coating materials: RE3NbO7 (RE = La, Nd, Sm, Eu, Gd, Dy) ceramics. J Am Ceram Soc 2018, 101: 4503-4508.
Zheng Q, Chen L, Song P, et al. Potential thermal barrier coating materials: RE2FeTaO7 (RE = Y, Eu, Gd, Dy) compounds. J Alloys Compd 2021, 855: 157408.
Ren XM, Tian ZL, Zhang J, et al. Equiatomic quaternary (Y1/4Ho1/4Er1/4Yb1/4)2SiO5 silicate: A perspective multifunctional thermal and environmental barrier coating material. Scripta Mater 2019, 168: 47-50.
Chen L, Hu MY, Guo J, et al. Mechanical and thermal properties of RETaO4 (RE = Yb, Lu, Sc) ceramics with monoclinic-prime phase. J Mater Sci Technol 2020, 52: 20-28.
Zhu JT, Meng XY, Xu J, et al. Ultra-low thermal conductivity and enhanced mechanical properties of high-entropy rare earth niobates (RE3NbO7, RE = Dy, Y, Ho, Er, Yb). J Eur Ceram Soc 2021, 41: 1052-1057.
Dehkharghani AMF, Rahimipour MR, Zakeri M. Improving the thermal shock resistance and fracture toughness of synthesized La2Ce2O7 thermal barrier coatings through formation of La2Ce2O7/YSZ composite coating via air plasma spraying. Surf Coat Technol 2020, 399: 126174.
Journal of Advanced Ceramics
Pages 615-628
Cite this article:
XUE Y, ZHAO X, AN Y, et al. High-entropy (La0.2Nd0.2Sm0.2Eu0.2Gd0.2)2Ce2O7: A potential thermal barrier material with improved thermo-physical properties. Journal of Advanced Ceramics, 2022, 11(4): 615-628.








Web of Science






Received: 27 July 2021
Revised: 06 December 2021
Accepted: 10 December 2021
Published: 03 March 2022
© The Author(s) 2021.

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made.

The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder.

To view a copy of this licence, visit