Single-phase formation mechanism and dielectric properties of sol-gel-derived Ba(Ti_(0.2)Zr_(0.2)Sn_(0.2)Hf_(0.2)Ce_(0.2))O_(3) high-entropy ceramics  

作　　者：Jia Liu Cuiying Ma Lianli Wang Ke Ren Hongpei Ran Danni Feng Huiling Du Yiguang Wang 

机构地区：[1]College of Materials Science and Engineering,Xi’an University of Science and Technology,Xi’an 710054,China [2]Institute of Advanced Structure Technology,Beijing Institute of Technology,Beijing 100081,China [3]State Key Laboratory of Advanced Materials and Electronic Components,Guangdong Fenghua Advanced Technology Holding Co.,Ltd.,Zhaoqing 526020,China

出　　处：《Journal of Materials Science & Technology》2022年第35期103-111,共9页材料科学技术（英文版）

基　　金：financially supported by the National Natural Science Foundation of China (Nos.52102144,52172099);the Provincial Joint Fund of Shaanxi (No.2021JLM-28);the Natural Science Basic Research Plan in Shaanxi Province of China (No.2022JM-255);the Scientific Research Plan Projects of Shaanxi Education Department (No.19JK0525)。

摘　　要：Single-phase Ba(Ti_(0.2)Zr_(0.2)Sn_(0.2)Hf_(0.2)Ce_(0.2))O_(3)(BTZSHC) high-entropy ceramics(HECs) with the perovskite structure were successfully prepared via the sol-gel method.The results reveal that the as-prepared ceramics exhibit a single cubic phase belonging to the Pm3 m space group.The high entropy is the driving force of the formation of single-phase ceramics.A larger entropy(ΔS_(mix)) and a negative enthalpy(ΔH_(mix)) are conducive to the formation of single-phase compounds.Herein,ΔS_(mix)=0.323 R mole-1andΔH_(mix)=43.88 kJ/mol.The sluggish-diffusion effect ensures the thermal stability of high-entropy systems.Dielectric measurements reveal that the as-prepared BTZSHC high-entropy ceramics are relaxor ferroelectrics,and the degree of relaxor(γ) is 1.9.The relaxor behavior of the as-prepared ceramics can be ascribed to the relaxation and thermal evolution of their polar units(PUs).The findings of this work provide a theoretical basis and technical support for the preparation of single-phase high-entropy ceramics.

关 键 词：High-entropy ceramics Single-phase formation mechanism Perovskite structure Sol-gel method Dielectric properties 

分 类 号：TQ174.1[化学工程—陶瓷工业]