Enhanced thermoelectric performance of Cu2Se realized by Ag2S doping
Publication Name
Physica B: Condensed Matter
Abstract
In this paper, Cu2Se samples doped with different concentrations of Ag2S were prepared by mechanical alloying and spark plasma sintering. Ag and S elements diffused during the preparation process and appeared aggregation in EDS mapping images. AgCuSe impurity phase can be observed in Cu2Se samples after Ag2S doping. Because of the enhanced scattering of the low- and mid-frequency phonons by AgCuSe nano inclusion, the total thermal conductivity of the Ag2S doped samples exhibits a significant decrease. Additionally, the diffusion and substitution of S can efficiently impede the formation of Cu vacancies. Ag ions can also fill the Cu vacancies, leading to the decreasing carrier concentration. Finally, the thermoelectric property is improved and the maximum ZT value ∼1.5 is achieved at 820 K in Cu2Se/ 2% Ag2S, which is about 1.5 times of the undoped Cu2Se sample.
Open Access Status
This publication is not available as open access
Volume
654
Article Number
414725
Funding Number
U1504511
Funding Sponsor
National Natural Science Foundation of China