BiCuSeO/Ag复合材料的制备与热电性能  

Preparation and Thermoelectric Properties of BiCuSeO/Ag Composites

作　　者：刘思怡 王宇杭 李洪涛 朱红玉 黄伟 秦丙克 宿太超 LIU Siyi;WANG Yuhang;LI Hongtao;ZHU Hongyu;HUANG Wei;QIN Bingke;SU Taichao(College of Science,Guilin University of Technology,Guilin 541006,Guangxi,China;Shanghai Customs District of P.R.China,Shanghai 200135,China;School of Chemistry and Materials Engineering,Liupanshui Normal University,Liupanshui 553004,Guizhou,China)

机构地区：[1]桂林理工大学理学院,广西桂林541006 [2]中华人民共和国上海海关,上海200135 [3]六盘水师范学院化学与材料工程学院,贵州六盘水553004

出　　处：《陶瓷学报》2022年第3期428-432,共5页Journal of Ceramics

基　　金：广西自然科学基金(2021GXNSFAA220064);广西科技基地和人才专项(桂科AD20297001,桂科AD20297014);国家自然科学基金(52062031);大学生创新创业项目(202110596216,202110596636)。

摘　　要：具有天然超晶格结构的四元化合物BiCuSeO具有极低的热导率和较大的Seebeck系数,但较低的电导率影响了其热电性能。利用二次固相反应方法制备了BiCuSeO,并以Ag_(2)O为前驱物,采用无压烧结方法制备了Ag复合的BiCuSeO基热电陶瓷。考察了Ag_(2)O的添加量对BiCuSeO的微观结构与电声输运特性的影响。结果表明:无压烧结样品中Ag主要以单质形式与BiCuSeO复合,同时,少量Ag以离子形式进入基体材料的晶格之中。Ag的复合和少量掺杂改变了BiCuSeO的导电机制并显著提升了电导率,而添加少量Ag_(2)O对BiCuSeO的Seebeck系数和热导率影响较小。添加1 wt.%的Ag_(2)O样品的品质因子Z值在室温条件下达到1.5×10^(-4)K^(-2),约为BiCuSeO的20倍。因此,Ag复合有助于提高BiCuSeO的热电性能。Quaternary compound BiCuSeO,with natural superlattice structure,has extremely low thermal conductivity and high Seebeck coefficient,but its thermoelectric properties are restricted by its low electrical conductivity.In this study,BiCuSeO was prepared by using solid state reaction method and BiCuSeO/Ag composites were pr epared by using pressureless sintering process with Ag_(2)O as precursor.The effects of Ag_(2)O on microstructure and thermoelectric properties of BiCuSeO were studied.It was found that Ag was mainly present in the form of metal after the pressureless sintering process,while a small fraction of Ag was incorporated into the crystal structure of BiCuSeO.While the addition of Ag varied the conduction mechanism of BiCuSeO and significantly enhanced the conductivity,it had almost no impact on the Seebeck coeffici ent and thermal conductivity.The figure of merit(Z)of the sample with 1 wt.%Ag_(2)O was 1.5×10^(-4)K^(-1) at room temperature,which is higher than that of BiCuSeO by about 20 times.Therefore,the incorporation of Ag is an effective way to improve the thermoelectric properties of BiCuSeO ceramics.

关 键 词：固相反应 热电陶瓷 BiCuSeO 品质因子 

分 类 号：TQ174.75[化学工程—陶瓷工业]