Ultra-fast Synthesis of Cu2S Thermoelectric Materials under Pulsed Electric Field

doi:10.15541/jim20190096

Abstract

Abstract:

Cu₂S shows excellent thermoelectric properties as a material with phonon liquid-electron crystal characteristics. However, traditional preparation methods are cumbersome and difficult to afford bulk Cu₂S with uniform composition, high density and excellent thermoelectric properties. In this study, a novel method named Pulsed Electric Current Sintering was introduced to synthesize and sinter Cu₂S materials in one step consuming only 30 s. The synthesis of Cu₂S under intense pulsed electric field includes three steps. A small amount of CuS and Cu₂S forms in the first step; most of Cu₂S and part of Cu_1.96S are produced in the second step; finally, the remained Cu_1.96S and Cu react to form completely pure Cu₂S. The Cu₂S bulk obtained by this method is a dense bulk with homogeneous composition, and contained abundant multi-scale microstructures. The thermoelectric performance is optimized by regulation of Cu-deficient Cu_2-_xS. The maximum ZT of Cu_1.97S bulk at 873 K is 0.72, which is 49% higher than that of the pristine sample.

Key words: Cu₂S thermoelectric material, pulsed electric current, ultra-fast synthesis, Cu deficiency

CLC Number:

TN377

GONG Hao, SU Xian-Li, YAN Yong-Gao, TANG Xin-Feng. Ultra-fast Synthesis of Cu₂S Thermoelectric Materials under Pulsed Electric Field[J]. Journal of Inorganic Materials, 2019, 34(12): 1295-1300.

Figures/Tables 11

Fig. 1 Schematic diagram of sample sintering process

Fig. 2 Variations of current and temperature of DCS sample and PECS sample during the synthetic process

Fig. 3 Surfaces of both sides of a typical DCS sample in the current direction

Fig. 4 Surfaces of both sides of a typical PECS sample in the current direction

Fig. 5 XRD patterns of both sides of PECS sample and DCS sample

Fig. 6 XRD patterns of PECS samples prepared at different reaction time

Fig. 7 Profiles of the pulse current and sintering displacement varied with time

Fig. 8 Distribution mapping of element Cu (a) and S (b) on polished surface of PECS sample, with back scattering image (c) and chemical compositions (d) of the same area as above figures

Fig. 9 Secondary electron images of a fracture surface of PECS sample on different magnification scales

Fig. 10 XRD patterns of PECS-Cu2-xS(0<x≤0.2)

Fig. 11 Temperature dependence of heat capacity(a), thermal diffusivity(b) of PECS-Cu2S, and electrical conductivity (c), Seebeck coefficient (d), thermal conductivity (e), ZT (f) of PECS-Cu2-xS

References 16

[1]	HE J, TRITT T M . Advances in thermoelectric materials research: looking back and moving forward. Science, 2017, 357(6358): eaak9997.
[2]	TAN G, ZHAO L D, KANATZIDIS M G . Rationally designing high-performance bulk thermoelectric materials. Chemical Reviews, 2016,116(19):12123.
[3]	BULAT L P, IVANOV A A, OSVENSKII V B , et al. Thermal conductivity of Cu₂Se taking into account the influence of mobile copper ions. Physics of the Solid State, 2017,59(10):2097-2102.
[4]	SUN Y, XI L, YANG J , et al. The "electron crystal" behavior in copper chalcogenides Cu₂X(X=Se, S). Journal of Materials Chemistry A, 2017,5(10):5098-5105.
[5]	YU J, ZHAO K, QIU P , et al. Thermoelectric properties of copper- deficient Cu₂-_xSe (0.05≤x≤0.25) binary compounds. Ceramics International, 2017,43(14):11142-11148.
[6]	LIANG X . Mobile copper ions as heat carriers in polymorphous copper sulfide superionic conductors. Applied Physics Letters, 2017,111(13):133902.
[7]	ROY P, SRIVASTAVA S K . Nanostructured copper sulfides: synthesis, properties and applications. CrystEngComm, 2015,17(41):7801-7815.
[8]	HE X F, ZHU Y Z, MO Y F . Origin of fast ion diffusion in super- ionic conductors. Nature Communications, 2017,8:15893.
[9]	SUN S, LI P, LIANG S , et al. Diversified copper sulfide (Cu₂-_xS) micro-/nanostructures: a comprehensive review on synthesis, modifications and applications. Nanoscale, 2017,9(32):11357.
[10]	TANG Y Q, GE Z H, FENG J . Synthesis and thermoelectric properties of copper sulfides via solution phase methods and spark plasma sintering. Crystals, 2017,7(5):141.
[11]	YAO Y, ZHANG B P, PEI J , et al. Thermoelectric performance enhancement of Cu₂S by Se doping leading to a simultaneous power factor increase and thermal conductivity reduction. Journal of Materials Chemistry C, 2017,5(31):7845-7852.
[12]	ZHANG X X, WANG W, XIE S H , et al. Thermoelectric performance of Cu₂S prepared by hydrothermal method. Functional Materials, 2017,48(11):11197.
[13]	HE Y, DAY T, ZHANG T S , et al. High thermoelectric performance in non-toxic earth-abundant copper sulfide. Advanced Materials, 2014,26(23):3974-3978.
[14]	YANG D W, SU X L, YAN Y G , et al. Mechanochemical synthesis of high thermoelectric performance bulk Cu₂X (X=S, Se) materials. APL Materials, 2016,4(11):116110.
[15]	ZHENG L J, ZHANG B P, LI H Z , et al. Cu_xS superionic compounds: electronic structure and thermoelectric performance enhancement. Journal of Alloys and Compounds, 2017,722:17-24.
[16]	DENNLER G, CHMIELOWSKI R, JACOB S , et al. Are binary copper sulfides/selenides really new and promising thermoelectric materials? Advanced Energy Materials, 2014,4(9):1301581.

Ultra-fast Synthesis of Cu₂S Thermoelectric Materials under Pulsed Electric Field

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