Sol-gel auto-combustion synthesis of K_xNa_(1-x)NbO_3 nanopowders and ceramics: Dielectric and piezoelectric properties  

溶胶凝胶自蔓延燃烧法合成K_xNa_(1-x)NbO_3纳米粉体及陶瓷:介电和压电性能（英文）

作　　者：Hua-lei CHENG Jian XIAO Peng GAO Yun-yun YAN Shuan-ping GAO Hong-liang DU 程花蕾;肖健;高鹏;严云云;高拴平;杜红亮(宝鸡文理学院化学化工学院陕西省植物化学重点实验室,宝鸡721013;西北工业大学材料学院凝固技术国家重点实验室,西安710072;空军工程大学理学院,西安710051)

机构地区：[1]Key Laboratory of Phytochemistry of Shaanxi Province,College of Chemistry and Chemical Engineering,Baoji University of Arts and Sciences,Baoji 721013,China [2]State Key Laboratory of Solidification Processing,School of Materials Science and Engineering Northwestern Polytechnical University,Xi’an 710072,China [3]Science College,Air Force Engineering University,Xi’an 710051,China

出　　处：《Transactions of Nonferrous Metals Society of China》2018年第9期1801-1807,共7页中国有色金属学报（英文版）

基　　金：Project(21501007)supported by the National Natural Science Foundation of China;Project(2016GY-226)supported by the Industrial Science and Technology Plan in Shaanxi Province of China;Project(ZK15044)supported by the Doctoral Scientific Research Starting Foundation of Baoji University of Arts and Sciences,China;Project(201610721039)supported by Undergraduate Training Programs for Innovation and Entrepreneurship,China

摘　　要：The KxNa1-xNbO3 nanopowders with cubic-like morphology and an average size of about 50 nm were synthesized by sol-gel auto-combustion method.And then,the ceramics were prepared and the phase transition,microstructure and electrical properties of the KxNa1-xNbO3 ceramics were investigated.Pure perovskite phases of the KxNa1-xNbO3 ceramics were confirmed by XRD patterns and the K0.50Na0.50NbO3 ceramics show the coexistence of orthorhombic and monoclinic structures.SEM micrographs show that all samples have bimodal grain size distributions and the number of the small grains decrease with increasing K+content in the bimodal grain size distribution system.The K0.50Na0.50NbO3 ceramics with the uniform grain size and the maximum density show excellent electrical properties withεr=467.40,tanδ=0.020,d33=128 pC/N and kp=0.32 at the room temperature,demonstrating that the properties of the K0.50Na0.50NbO3 powers prepared by sol-gel auto-combustion are excellent and the ceramics are promising lead-free piezoelectric materials.室温下用溶胶凝胶自蔓延燃烧法合成平均尺寸约50 nm的仿立方体结构K_(x )Na_(1-x )Nb O_3纳米粉体并制备成陶瓷,对陶瓷进行相结构、显微组织以及电性能的表征。XRD结果表明,K_(x )Na_(1-x )NbO_3陶瓷为纯的钙钛矿结构,且K_(0.5)Na_(0.5)Nb O_3陶瓷具有正交相和单斜相的混合相结构。SEM结果表明,所有陶瓷样品均为孪晶分布,且孪晶分布中小晶粒数随K^+含量的增加而减少。在室温下,晶粒尺寸均匀且具有最大密度的K_(0.5)Na_(0.5)Nb O_3陶瓷具有较优异的电性能:ε_r=467.40,tanδ=0.020,d_(33)=128 pC/N,k_p=0.32。K_(0.5)Na_(0.5)Nb O_3陶瓷的优良电性能说明溶胶凝胶自蔓延燃烧法合成的K_(0.50)Na_(0.50)Nb O_3粉体性能较好,且制备的陶瓷满足无铅压电材料应用。

关 键 词：sol-gel auto-combustion KxNa1-xNbO3 phase transition MICROSTRUCTURE electrical properties 

分 类 号：TQ174.1[化学工程—陶瓷工业]