Year: 1999
Type: article
Abstract: ＊＊＊翫陀s∫α7￠Pθ砂彰。乃π￠らS％即勉α吻ゴ」々％，7b厘yoエ67-002エ ＊＊＊＊D￠μ〃勿zθ7z ρプE窺雇η)％窺θ％たzZ C乃θ〃2ゴαz1五：π8z ％θθ7勿g；1動gαん勿∫％こ乃z勿θ駕∫ちノ，、口lz6ぬゴqノ」，てτb々ソ。エ92-0015 ＊＊＊零＊A娩ガ。ノ￠σ1R6sθα7℃乃乃￠3 髭％-冶プb7ル働旋zな，7蓉％ん％うα305-0047 Sintered PbTe．materials with average grain sizes of 28-309μm were prepared by spark plasma sintering technique． The apparent densities of the sintered PbTe were 8．17-8。23 Mg／m3， which were higher than 99％of the theoretical one． Thermoelectric properties of the sintered materials and the as-grown boule by Bridgman method were lneasured in the temperature range from 77 to 350 K． Resistivity，ρ， of the sintered materials increased with decreasing grain size． Temperature dependence Qfρof the sintered PbTe was remarkably different from that Qf the as-grown boule below 250 K because of potential barriers at grain boundaries． Hall coefficient， RH， of the sintered materials at room temperature increased from 1。4×10-6 to 3．4×10-6m3／C， as the average grain size increased from 28 to 309μm， which suggested that oxidation in the crystal grains was caused in the sintering process． Temperature dependence of the thermoelectric power，α， of the sintered PbTe below 250 K reflected the effect of carrier scattering at grain boundaries． Lattice thermal conductivity of the sintered PbTe decreased with decreasing grain size below 250 K， while it was independent of the grain size above that temperature． Above 250 K，thermoelectric properties of the sintered PbTe except those in the 28μm grain case were consistent with those of the as-grown boule． The values ofαand RH at 295 K were calculated by using a two-valence-band model involving a non-parabolic and a parabolic valence band． The calculation results were in good agreement with the experimental data． (Recelved June 14，1999；In Final Form August 4，1999) 挽〃ωor爵：髭α4観勉磁θ，地θ㎜擁伽6ρ吻鋤，伽辮σJ cO漁田下吻漉伽S〃ZαSゴ漉漉8 ρ0伽拡α1うαγ7畝魏0-0α纏α-一うα％4彫04θ加0卿α鵤うoZ伽α勧α加運転励01ゴ60α勧66伽4 1．緒 言
Authors: Seiji Yoneda, Eiji Ohta, Hiromasa T. Kaibe, Isao J. Ohsugi, Ichiro Shiota, Isao A. Nishida
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2607043867