Thermoelectric Properties of Ag-doped In4Se2.95 Polycrystalline Compounds
陈燕春;刘鹏飞;陈玲;吴立明
a (Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China)
b (Key Laboratory of Optoelectronic Materials Chemistry and Physics, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China)
c (School of Physical Science and Technology, Shanghai Tech University, Shanghai 201210, China)
Thermoelectric Properties of Ag-doped In4Se2.95 Polycrystalline Compounds
CHEN Yan-Chun;LIU Peng-Fei;CHEN Ling;WU Li-Ming
a (Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China)
b (Key Laboratory of Optoelectronic Materials Chemistry and Physics, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China)
c (School of Physical Science and Technology, Shanghai Tech University, Shanghai 201210, China)
In4Se3-based materials are noticeable n-type thermoelectric materials because of lead-free and intrinsically low lattice thermal conductivity, but the In4Se3-δ crystals (with Se-deficiency, δ) suffer strong anisotropy and cleavage habit. Thus the researches on polycry- stalline In4Se3-based materials are of great importance. Herein, we experimentally and theoretically investigated the thermoelectric properties of In4-xSe2.95Agx polycrystalline compounds. Ag occupying the intercalation or In4 site is energetically most favorable in light of the density functional theory calculation. The maximum solubility of Ag (xm) is very low (xm < 0.03) and the experimental result indicates that the electrical transport behavior of In4-xSe2.95Agx compounds is not significantly optimized by Ag-dopant. Consequently, a maximum ZT of 0.92 at 723 K is obtained by In3.98Se2.95Ag0.02 compound that represents 15% enhancement over that of the un-doped one which benefits from the slightly enhanced power factor and the reduced total thermal conductivity.
In4Se3-based materials are noticeable n-type thermoelectric materials because of lead-free and intrinsically low lattice thermal conductivity, but the In4Se3-δ crystals (with Se-deficiency, δ) suffer strong anisotropy and cleavage habit. Thus the researches on polycry- stalline In4Se3-based materials are of great importance. Herein, we experimentally and theoretically investigated the thermoelectric properties of In4-xSe2.95Agx polycrystalline compounds. Ag occupying the intercalation or In4 site is energetically most favorable in light of the density functional theory calculation. The maximum solubility of Ag (xm) is very low (xm < 0.03) and the experimental result indicates that the electrical transport behavior of In4-xSe2.95Agx compounds is not significantly optimized by Ag-dopant. Consequently, a maximum ZT of 0.92 at 723 K is obtained by In3.98Se2.95Ag0.02 compound that represents 15% enhancement over that of the un-doped one which benefits from the slightly enhanced power factor and the reduced total thermal conductivity.
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2016, Vol. 35 
