B掺杂调控Si_(0.85)Ge_(0.15)合金的热电性能研究  

Research on thermoelectric properties ofSi_(0.85)Ge_(0.15) alloy controlled by B doping

作　　者：景丹阳 李杰[2] 程展旗 况菁 段兴凯 JING Danyang;LI Jie;CHENG Zhanqi;KUANG Jing;DUAN Xingkai(School of Materials and Engineering,Jiujiang University,Jiujiang 332005,China;School of Physics and Materials,Nanchang University,Nanchang 330031,China)

机构地区：[1]九江学院材料科学与工程学院,江西九江332005 [2]南昌大学物理与材料院,江西南昌330031

出　　处：《功能材料》2024年第11期11182-11187,共6页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(51461021);国家级大学生创新创业项目(202311843013)。

摘　　要：SiGe合金是重要的高温热电材料,其热电性能的优化一直备受关注。采用电弧熔炼和热压烧结成功制备了Si_(0.85)Ge_(0.15) B x(x=0.01,0.015,0.04,0.045,0.05,0.06)合金。利用X射线衍射技术、扫描电子显微镜并结合能谱技术对样品的物相结构、微观形貌和化学成分进行了表征。研究了B掺杂对Si_(0.85)Ge_(0.15)合金的电热输运性能影响。研究表明,在300~950 K的温度范围内,塞贝克系数均为正值,表明了P型半导体特性,且随温度的升高,塞贝克系数增大。随着B掺杂浓度的增加,电导率逐渐增加,塞贝克系数则不断降低。在950 K时,Si_(0.85)Ge_(0.15) B 0.01样品的塞贝克系数最大,温度为750 K时,B掺杂含量为0.04的样品功率因子具有最大值,为1.72×10^(-3) Wm^(-1)·K^(-2),900 K时,B掺杂含量为0.04的样品ZT值达到了0.4,相比于B掺杂含量为0.01的样品,其热电性能提升了约1.5倍。SiGe alloy is an important high-temperature thermoelectric material,and the optimization of its thermoelectric properties has attracted more attention.In this paper,Si_(0.85)Ge_(0.15) B x(x=0.01,0.015,0.04,0.045,0.05,0.06)alloys were successfully prepared using arc melting and hot pressing.The phase structure,microstructure and chemical composition of the samples were characterized by X-ray diffraction(XRD),electron scanning microscopy(SEM)and energy dispersive spectroscopy(EDS).The effects of B doping on the electrical and thermal transport properties of Si_(0.85)Ge_(0.15) alloy were investigated.The results show that in the temperature range of 300 K to 950 K,the Seebeck coefficients are positive,which indicates the characteristics of P-type semiconductor.The Seebeck coefficient increases with the increase of temperature.With the increase of B doping concentration,the electrical conductivity increases gradually,and the Seebeck coefficient decreases continuously.At 950 K,the Seebeck coefficient of Si_(0.85)Ge_(0.15) B 0.01 sample has the largest value.When the temperature is 750 K,the power factor of the sample with B content of 0.04 has the maximum value of 1.72×10^(-3)/(Wm^(-1)·K^(2)).At 900 K,the ZT value of the sample with B doping content of 0.04 reaches 0.4,which is about 1.5 times higher than that of the sample with B doping content of 0.01.

关 键 词：硅锗合金 电导率 塞贝克系数 硼掺杂 晶格热导率 

分 类 号：TB34[一般工业技术—材料科学与工程]