Thermoelectric properties of BixSb2-xTe3 alloy with layered microstructure optimized by microwave hot pressing
LIU Peihai1,2, FENG Bo1,2, HU Xiaoming1,2, LI Rusong1,2, ZHANG Yanglin1,2, FAN Xi'an1,2
1. The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081, China; 2. Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, Wuhan 430081, China
Abstract The p-type BixSb2-xTe3 alloys with hierarchical microstructures were prepared by mechanical alloying and a new sintering technique of microwave activated hot pressing (MAHP). The effects of Bi content on the microstructure and thermoelectric properties of BixSb2-xTe3 alloy were studied. The results show that there are irregular nanoparticles, which are in-situ nanostructures caused by microwave arc effect. With increasing Bi content, the electrical resistivity and Seebeck coefficient increase due to the obvious decrease of carrier concentration. At the same time, the lattice thermal conductivity increases due to the decrease in the amount of irregular nanograins. BixSb2-xTe3 has a maximum power factor of 3.81 mW/(m·K2) and a minimum lattice thermal conductivity of 0.33 W/(m·K), so as to obtain the maximum dimensionless figure of merit value of 1.23 at 70 ℃. The MAHP technique introduced in this work has achieved a significant improvement in the thermoelectric properties of the BixSb2-xTe3 alloy.
LIU Peihai,FENG Bo,HU Xiaoming, et al. Thermoelectric properties of BixSb2-xTe3 alloy with layered microstructure optimized by microwave hot pressing[J]. Materials Science and Engineering of Powder Metallurgy, 2020, 25(3): 213-220.
[1] XU Z J, WU H J, ZHU J, et al.Attaining high mid-temperature performance in (Bi,Sb)2Te3 thermoelectric materials via synergistic optimization[J]. NPG Asia Mater, 2016, 8(9): e302. [2] TANG Z L, HU L P, ZHU T J, et al.High performance n-type bismuth telluride based alloys for mid-temperature power generation[J]. J Mater Chem C, 2015, 3(40): 10597-10603. [3] BARAKO M T, PARK W, MARCONNET A M, et al.Thermal cycling, mechanical degradation, and the effective figure of merit of a thermoelectric module[J]. J Electron Mater, 2013, 42(3): 372-381. [4] KIM M Y, OH T S.Thermoelectric power generation characteristics of a thin-film device consisting of electrodeposited n-Bi2Te3 and p-Sb2Te3 thin-film legs[J]. J Electron Mater, 2013, 42(9): 2752-2757. [5] DRESSELHAUS M S, CHEN G, et al.New directions for low-dimensional thermoelectric materials[J]. Adv Mater, 2007, 19(8): 1043-1053. [6] MINNICH A J, DRESSELHAUS M S, REN Z F, et al.Bulk nanostructured thermoelectric materials: current research and future prospects[J]. Energ Environ Sci, 2009, 2(5): 466-479. [7] XIAO Y, YANG J Y, JIANG Q H, et al.A simultaneous increase in the ZT and the corresponding critical temperature of p-type Bi0.4Sb1.6Te3 by a combined strategy of dual nanoinclusions and carrier engineering[J]. J Mater Chem A, 2014, 2(47): 20288-20294. [8] MEHTA R J, ZHANG Y, KARTHIK C, et al.A new class of doped nanobulk high-figure-of-merit thermoelectrics by scalable bottom-up assembly[J]. Nat Mater, 2012, 11(3): 233-240. [9] HU L P, LIU X M, XIE H H, et al.Improving thermoelectric properties of n-type bismuth-telluride-based alloys by deformation-induced lattice defects and texture enhancement[J]. Acta Mater, 2012, 60(11): 4431-4437. [10] XIE W, HE J, KANG H J, et al.Identifying the specific nanostructures responsible for the high thermoelectric performance of (Bi,Sb)2Te3 nanocomposites[J]. Nano lett, 2010, 10(9): 3283-3289. [11] JIANG Q H, YAN H X, KHALIQ J, et al.Large ZT enhancement in hot forged nanostructured p-type Bi0.5Sb1.5Te3bulk alloys[J]. J Mater Chem A, 2014, 2(16): 5785-5790. [12] OGHBAEI M, MIRZAEE O.Microwave versus conventional sintering: A review of fundamentals, advantages and applications[J]. J Alloy Compd, 2010, 41(21): 175-189. [13] JOHNSON D L.Microwave and plasma sintering of ceramics[J]. Ceram Int, 1991, 17(5): 295-300. [14] ROY R, AGRAWAL D, CHENG J P, et al.Full sintering of powdered-metal bodies in a microwave field[J]. Nature, 1999, 399(6737): 668-670. [15] SAITOU K.Microwave sintering of iron, cobalt, nickel, copper and stainless steel powders[J]. Scripta Mater, 2006, 54(5), 875-879. [16] YADOJI P, PEELAMEDU R, AGRAWAL D, et al.Microwave sintering of Ni-Zn ferrites: comparison with conventional sintering[J]. Mater Sci Eng B, 2003, 98(3): 269-278. [17] BREVAL E, CHENG J P, AGRAWAL D K, et al.Comparison between microwave and conventional sintering of WC/Co composites[J]. Mater Sci Eng A, 2005, 391(1): 285-295. [18] DELAIZIR G, BERNARD-GRANGER G, MONNIER, et al. A comparative study of spark plasma sintering (SPS), hot isostatic pressing (HIP) and microwaves sintering techniques on p-type Bi2Te3 thermoelectric properties[J]. Mater Res Bull, 2012, 47(8): 1954-1960. [19] YANG F, FAN X A, RONG Z Z, et al.Lattice thermal conductivity reduction due to in situ-generated nano-phase in Bi0.4Sb1.6Te3 alloys by microwave-activated hot pressing[J]. J Electron Mater, 2014, 43(11): 327-4334. [20] KADHIM A, HMOOD A, HASSAN H A.Effect of Se substitution on structural and electrical transport properties of Bi0.4Sb1.6Se3xTe3(1-x) hexagonal rods[J]. J Electron Mater, 2013, 42(6): 1017-1023. [21] DI L I, SUN, QIN R X. Improving thermoelectric properties of p-type Bi2Te3-based alloys by spark plasma sintering[J]. Prog Nat Sci Mater Int, 2011, 21(4): 336-340. [22] HWANG C W, HYUN D B, HA H P, et al.Effects of excess Te on the thermoelectric properties of p-type 25% Bi2Te3-75% Sb2Te3 single crystal and hot-pressed sinter[J]. J Mater Sci, 2001, 36(13): 3291-3297. [23] ZHAO L D, ZHANG B P, LIU W S, et al.Effect of mixed grain sizes on thermoelectric performance of Bi2Te3 compound[J]. J Appl Phys, 2009, 105(2): 023704. [24] XIE W, TANG X, YAN Y, et al.Unique nanostructures and enhanced thermoelectric performance of melt-spun BiSbTe alloys[J]. Appl Phys Lett, 2009, 94(10): 139-141. [25] JIANG C P, FAN X A, FENG B, et al.Thermal stability of p-type polycrystalline Bi2Te3-based bulks for the application on thermoelectric power generation[J]. J Alloys Compd, 2017, 692(1): 885-891. [26] WANG S, XIE W, LI H, et al.High performance n-type (Bi,Sb)2(Te,Se)3 for low temperature thermoelectric generator[J]. J Phys D (Appl Phys), 2010, 43(33): 335404.
2020, Vol. 25 
