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用熔融法结合放电等离子烧结(SPS)合成了Yb/Sr双原子复合填充的n型YbxSr8-xGa16Ge30(x=0,0.5,1.0,1.5)笼合物,研究了双原子复合填充及Yb填充量x对YbxSr8-xGa16Ge30笼合物热电传输特性的影响规律.结果表明,Yb在YbxSr8-xGa16Ge30化合物中的固溶极限介于1.0—1.5之间.随着Yb填充量x的增加,化合物的室温载流子浓度增加而迁移率降低.在300—800K温度范围内,随着x的增加,双原子填充试样的电导率逐渐增大,Seebeck系数逐渐减小,其中x=0.5的试样与单原子填充的Sr8Ga16Ge30试样相比,电导率变化不大,Seebeck系数显著增加.Yb/Sr双原子复合填充比Sr单原子填充更有利于晶格热导率的降低,且晶格热导率随着Yb填充量x的增加逐渐降低.在所有n型YbxSr8-xGa16Ge30化合物中,Yb1.0Sr7.0Ga16Ge30化合物的ZT值最大,在800K时其最大ZT值达0.81,与单原子填充的Sr8Ga16Ge30化合物相比ZT值提高了35%.
The n-type YbxSr8-xGa16Ge30 (x = 0,0.5,1.0,1.5) composite filled with Yb / Sr double-atoms was synthesized by melt method combined with spark plasma sintering (SPS) x on the thermoelectric properties of the YbxSr8-xGa16Ge30 composite was investigated.The results show that the solid solution limit of Yb in the YbxSr8-xGa16Ge30 compound is between 1.0 and 1.5. With the increase of the Yb filling amount x, At the temperature range of 300-800K, the conductivity of double-atom-filled samples increases gradually and the Seebeck coefficient decreases gradually with the increase of x, where the sample with x = 0.5 and the single Compared with the atom-filled Sr8Ga16Ge30 samples, the conductivity did not change much and the Seebeck coefficient increased significantly. The Yb / Sr double-atom packing was more favorable for the reduction of lattice thermal conductivity than the Sr single-atom packing, and the lattice thermal conductivity The Yb1.0Sr7.0Ga16Ge30 compound has the largest ZT value for all n-type YbxSr8-xGa16Ge30 compounds and has a maximum ZT value of 0.81 at 800K compared with that of the monatomic filled Sr8Ga16Ge30 compound ZT value increased by 35%.