Low thermal conductivity in nanoscale layered materials synthesized by the method of modulated elemental reactants
Low thermal conductivity in nanoscale layered materials synthesized by the method of modulated elemental reactants
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DOI：
10.1063/1.2967722
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发表时间：
2008-08-01
影响因子：
3.2
通讯作者：
Boettner, Harald
中科院分区：
文献类型：
--
作者：
Chiritescu, Catalin;Cahill, David G.;Boettner, Harald
我们报道了用调制单质反应物法合成的多层薄膜[(TiTe(2))(3)(Bi(2)Te(3))(x)(TiTe(2))(3)(Sb(2))(3))(y)](i) （x=1-5, y=1-5）和非拟合层二硫化物薄膜[(PbSe)(m)(TSe(2))(n)](i) （T=W或Mo， m=1-5, n=1-5）的室温、平面导热系数和纵向声速。这些纳米级层状材料的热导率低于组分化合物的预测最小热导率：比多层[(TiTe(2))(3)(Bi(2)Te(3))(x)(TiTe(2))(3)(Sb(2))Te(3))(y)](i)薄膜的Bi(2)Te(3)](i)薄膜的最小热导率低两倍，比非贴合层二硫族化合物[(PbSe)(m)(TSe2)(n)](i)的最小热导率低五到六倍。我们将低导热归因于层状晶体的各向异性键合和层状晶体沿垂直于表面方向堆积的取向紊乱。(C) 2008年美国物理研究所。
We report the room-temperature, cross-plane thermal conductivities, and longitudinal speeds of sound of multilayer films [(TiTe(2))(3)(Bi(2)Te(3))(x)(TiTe(2))(3)(Sb(2)Te(3))(y)](i) (x=1-5, y=1-5) and misfit-layer dichalcogenide films [(PbSe)(m)(TSe(2))(n)](i) (T=W or Mo, m=1-5, and n=1-5) synthesized by the modulated elemental reactants method. The thermal conductivities of these nanoscale layered materials fall below the predicted minimum thermal conductivity of the component compounds: two times lower than the minimum thermal conductivity of Bi(2)Te(3) for multilayer [(TiTe(2))(3)(Bi(2)Te(3))(x)(TiTe(2))(3)(Sb(2)Te(3))(y)](i) films and five to six times lower than the minimum thermal conductivity of PbSe for misfit-layer dichalcogenides [(PbSe)(m)(TSe2)(n)](i). We attribute the low thermal conductivities to the anisotropic bonding of the layered crystals and orientational disorder in the stacking of layered crystals along the direction perpendicular to the surface. (C) 2008 American Institute of Physics.