[10a-N406-1~10] 9.4 Thermoelectric conversion

▲ [10a-N406-4] Optimizing the Condition for High Thermoelectric Performance of Flexible Ag₂(S_,Se) Material through Synergic Approach

〇(PC)Saurabh Singh^1,2, Keisuke Hirata¹, Masaharu Matsunami¹, Tsunehiro Takeuchi^1,2,3 (1.TTI Nagoya Japan, 2.CREST, Tokyo Japan., 3.MIRAI, Japan)

Keywords:Chalcogenides, Thermoelectrics, Flexible thermoelectric

Recently, Ag2S is found to be an interesting thermoelectric material with good flexibility. However, the value of ZT was found to be very low due to large electrical resistivity. To improve the ZT, the partial substitutions of Se, Te at sulfur site are investigated. Interestingly, the ductile nature of Ag2S material found to be excellent with Se substitutions at sulfur site compositions, and the maximum ZT of 0.6 at 300 K is achieved near room temperature. In this study, therefore, we modify the electronic structure of Ag2S1-xSex by non-toxic 3d transition metal elements substitution on Ag site. By this approach we successfully improve the S and achieved an effective increase of ZT near 300 K. We confirmed that n-type behavior was kept unchanged regardless of the substitutions. Notably, we found condition where S was increased while the small magnitudes of resistivity and k were maintained. As a result, large magnitudes both in power factor and ZT = 0.8 at 310 K, were obtained.