Synthesis and Characterization of Au nanoparticle-Supported Bulk Thermoelectric Materials

SbBiTe块状合金已成为室温下最有效的热电材料之一。另一方面，提高无因次优值（ZT）的方法是降低材料的晶格导热系数（κlat），同时保持高导电性，即创造声子散射而电子不受影响的情况。本文采用γ射线辐照法制备了完整的Au/AuTe_2纳米复合材料，其中Au/AuTe_2纳米颗粒均匀分布在Sb_<1.6>Bi_<0.4>Te_3基体中，没有聚集。这主要是由于纳米粒子与基体相之间声子散射界面数量的增加，从而导致ZT明显增强。在423 K时，Au/AuTe_2纳米颗粒负载的Sb_<1.6>Bi_<0.4>Te_3纳米复合材料的最大zt值为1.01，比Sb_<1.6>Bi_<0.4>Te_3纳米复合材料的最大zt值高约18%

SbBiTe bulk alloys have been some of the most efficient thermoelectric (TE) materials near room temperature. On the other hand, the way to enhance the dimensionless figure of merit (ZT) is to decrease the lattice thermal conductivity (κlat) of the material, while maintaining a high electrical conductivity, i.e., to create a situation in which phonons are scattered but electrons are unaffected. Here we synthesizeda complete nanocomposite using γ-ray irradiation, in which Au/AuTe_2 nanoparticles are dispersed uniformly without aggregation in the Sb_<1.6>Bi_<0.4>Te_3 matrix. The κlatwas significantly reduced mainly due to the increased number of interfaces for phonon scattering between the nanoparticles and the matrix phase, thereby resulting in clear enhancement of ZT. The maximum ZTvalue of the Au/AuTe_2 nanoparticle-supported Sb_<1.6>Bi_<0.4>Te_3 nanocomposite was 1.01 at 423 K, which is about 18% higher than the maximum Ztvalue of Sb_<1.6>Bi_<0.4>Te_3