采用溶胶-凝胶法制备了掺杂Sr, Li和Cu的Na1.4Co2O4基热电材料, 采用XRD分析了Na1.4Co2O4基热电材料的相组成.通过DTA-TG曲线确定材料的预烧结和终烧结温度分别为450和850 ℃. 研究了掺杂量对Na1.4Co2O4基材料电阻率、Seebeck系数和功率因子等热电性能的影响. 结果表明, 掺杂Li可降低Na1.4Co2O4的电阻率, 掺杂 Sr和Cu使材料的电阻率增加; 掺杂Li和Cu可大幅度提高Na1.4Co2O4的Seebeck系数和功率因子; 掺杂Sr的改善效果不显著, 掺杂Li的效果最好; 当Li掺杂量为0.40, Na1.4Co2O4基热电材料的功率因子在15℃时达到最大值 7444.73 μW?m-1?K-2.
Sr, Li and Cu-doped Na1.4Co2O4 based thermoelectric materials were prepared by sol-gel process. The phase constitution of Na1.4Co2O4 based thermoelectric materials was analyzed by XRD. According to DTA-TG curves, the pre-sintering and sintering temperatures of the materials were obtained to be 450 ℃ and 850 ℃, respectively. The influences of doping amount on the electrical resistivity, Seebeck coefficient and power factor of Na1.4Co2O4 based materials were investigated. The results showed that doping Li could decrease the electrical resistivity of Na1.4Co2O4, doping Sr and Cu could increase the electrical resistivity. Doping Li and Cu could improve the Seebeck coefficient and power factor of Na1.4Co2O4. The improving effect on Na1.4Co2O4 by doping Sr is not remarkable but by doping Li is the best. When 0.40 Li was doped, the power factor of Na1.0Li0.4Co2O4 at 15 ℃ reaches maximum value of 7444.73 μW?m-1?K-2.
[1] Ibrahim M M, Saleh S A, Ibrahim E M M, Hakeem A M A. J Alloys Compd, 2008; 452: 200
[2] Xiang P H, Kinemuchi Y, Kaga H, Watari K. J Alloys Compd, 2008; 454: 364
[3] Seetawan T, Amornkitbamrung V, Burinprakhon T, Maensiri S, Tongbai P, Kurosaki K, Muta H, Uno M, Yamanaka S. J Alloys Compd, 2008; 416: 291
[4] Cheng J G, Sui Y, Fu H J, Lu Z, Wei B, Qian Z N, Miao J P, Liu Z G, Huang X Q, Zhu R B, Wang X J, Su W H. J Alloys Compd, 2006; 407: 299
[5] Li Y, Xu G Y, Jiang M F. J Mater Sci Technol, 2006; 22: 526
[6] Li N, Jiang Y, Li G H,Wang C, Shi J F, Yu D B. J Alloys Compd, 2009; 467: 444
[7] Terassaki I, Sasago Y, Uchinokura K. Phys Rev, 1997; 56B: 12685
[8] Shi Y W, Qiao G J, Jin Z H. Rare Met Mater Eng, 2005; 34: 12
(石尧文, 乔冠军, 金志浩. 稀有金属材料与工程, 2005; 34: 12)
[9] Itoh T, Kawata T, Kitajima T, Terasaki I. Proc 17th Int Conf on Thermoelectrics, NJ: IEEE, 1998: 595
[10] Mrotzek A, M¨uller E, Plewa J. Proc 22nd Int Conf on Thermoelectrics, NJ: IEEE, 2003: 219
[11] Ito M, Nagira T, Furumoto D, Oda Y, Hara S. Sci Technol Adv Mater, 2004; 5: 125
[12] Motohashi T, Naujalis E, Veda R, Isawa K, Karppinen M, Yamauchi H. Appl Phys Lett, 2001; 79: 1480
[13] Wu D, Wang N L, Li G, Luo J L , Zheng P, Chen X H, Wang C H, Luo X G, Jin R, Mandrus D. J Phys Chem Solids, 2006; 67: 635
[14] Pei J, Chen G, Li X, Li Y X, Zhou N. Mater Lett, 2009; 63: 1459
[15] Yakabe H, Fujita K, Nakamura K, Kikuchi K. Proc 17th Int Conf on Thermoelectrics, NJ: IEEE, 1999: 551
[16] Cui Z Q, Liu B X. Metallography and Heat Treatment Principle. Harbin: Harbin Institute of Technology Press, 2001: 19
(崔忠圻, 刘北兴. 金属学与热处理原理. 哈尔滨: 哈尔滨工业大学出版社, 2001: 19)
[17] Zhong G X. Semiconductor Refrigeration and Its Application. Beijing: Science Press, 1989: 13, 190
(钟广学. 半导体制冷器件及其应用. 北京: 科学出版社, 1989: 13, 190)
[18] Park K, Jang K U, Kwon H C, Kim J G, Cho W S. J Alloys Compd, 2006; 419: 213
[19] Wang Y, Sui Y, Cheng J G, Wang X J, Miao J P, Liu Z G, Qian Z N, Su W H. J Alloys Compd, 2008; 448: 1
[20] Nagira T, Ito M, Katsuyama S, Majima K, Nagai H. J Alloys Compd, 2003; 348: 263
