| Autor: |
Shu W; National Laboratory of Solid-State Microstructures, Collaborative Innovation Center of Advanced Microstructures, and School of Physics, Nanjing University, Nanjing 210093, China., Tang Y; National Laboratory of Solid-State Microstructures, Collaborative Innovation Center of Advanced Microstructures, and School of Physics, Nanjing University, Nanjing 210093, China., Su B; National Laboratory of Solid-State Microstructures, Collaborative Innovation Center of Advanced Microstructures, and School of Physics, Nanjing University, Nanjing 210093, China., Hong A; School of Physics, Communication and Electronics, Jiangxi Normal University, Nanchang 330022, China., Lin L; Department of Applied Physics, College of Science, Nanjing Forestry University, Nanjing 210037, China., Zhou X; National Laboratory of Solid-State Microstructures, Collaborative Innovation Center of Advanced Microstructures, and School of Physics, Nanjing University, Nanjing 210093, China., Yan Z; National Laboratory of Solid-State Microstructures, Collaborative Innovation Center of Advanced Microstructures, and School of Physics, Nanjing University, Nanjing 210093, China., Liu JM; National Laboratory of Solid-State Microstructures, Collaborative Innovation Center of Advanced Microstructures, and School of Physics, Nanjing University, Nanjing 210093, China. |
| Abstrakt: |
Recently, the p-type semiconductor AgSbTe 2 has received a great deal of attention due to its promising thermoelectric performance in intermediate temperatures (300-700 K). However, its performance is limited by the suboptimal carrier concentration and the presence of Ag 2 Te impurities. Herein, we synthesized AgSb 1- x Cu x Te 2 ( x = 0, 0.02, 0.04, and 0.06) and investigated the effect of Cu doping on the thermoelectric properties of AgSbTe 2 . Our results indicate that Cu doping suppresses the Ag 2 Te impurities, raises the carrier concentration, and results in an improved power factor (PF). The calculation reveals that Cu doping downshifts the Fermi energy level, reduces the energy band gap and the difference among several valence band maximums, and thereby explains the improvement of PF. In addition, Cu doping reduces the thermal conductivity, possibly attributed to the inhibition of Ag 2 Te impurities and the phonon softening of the AgSb 1- x Cu x Te 2 . Overall, Cu doping improves the ZT of AgSb 1- x Cu x Te 2 . Among all samples, AgSb 0.96 Cu 0.04 Te 2 has a maximum ZT of ∼1.45 at 498 K and an average ZT of ∼1.11 from 298 to 573 K. |
