设计了一系列名义组成为Zn4Sb3-xInx(0~0.08, ?x=0.02)的In掺杂β-Zn4Sb3基块体材料, 并用真空熔融-随炉冷却-放电等离子体烧结工艺成功制备出无裂纹的In掺杂单相β--Zn4Sb3基块体材料. 300~700 K内材料的电热输运特性表明, In杂质对Zn4Sb3化合物的Sb位掺杂可导致载流子浓度和电导率大幅度增大、高温下本征激发几乎消失和晶格热导率显著降低, x=0.04和0.08的Zn4Sb3-xInx的In掺杂beta-Zn4Sb3化合物700K时晶格热导率均仅为0.21 W/(m·K). 与纯β-Zn4Sb3块体材料相比, 所有In掺杂β-Zn4Sb3基块体材料的ZT值均显著增大, x=0.06的Zn4Sb3-xInx的In掺杂β-Zn4Sb3基块体材料700K时ZT值达到1.13, 提高了69%.
A series of In-doped β-Zn4Sb3-based materials with nominal compositions of Zn4Sb3-xInx (0-0.08, ?x=0.02) by substituting Sb with In were designed in the paper. The single-phase In-doped β-Zn4Sb3-based bulk materials with no cracks were prepared by the combination of vacuum melting, furnace cooling and spark plasma sintering techniques. The electrical and thermal transport properties of Zn4Sb3-xInx in the temperature range of 300-700 K indicate that the In substitution for Sb in Zn4Sb3 compound brought the remarkable enhancement in carrier concentration and electrical conductivity, the almost complete vanishing of instinct excitation under high temperature, and the significant reduction in the lattice thermal conductivity. The lattice thermal conductivity for x=0.04 and 0.08 samples is very low and only about 0.21 W/(m·K) at 700 K. All In-doped β-Zn4Sb3-based bulk materials had higher ZT values as compared to undoped beta-Zn4Sb3 bulk material. A large ZT value of 1.13 has been achieved for Zn4Sb2.94In0.06 at 700 K that increased by 69%.
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