Electronic Transport and Thermoelectric Properties of Cu12-xZnxSb4S13 Tetrahedrites Prepared by Mechanical Alloying and Hot Pressing
Year: 2019
Type: article
Abstract: Tetrahedrite Cu 12 Sb 4 S 13 has low lattice thermal conductivity because of the lone-pair electrons of Sb, which cause the Cu atoms to vibrate at a low frequency and high amplitude.When the Cu atoms of Cu 12 Sb 4 S 13 are partially substituted with a transition metal, changes in the Cu vibrations can intensify phonon scattering, thereby enhancing the thermoelectric properties.The synthesis of tetrahedrite compounds by conventional melting methods requires sophisticated reactions because the S element vaporizes at low temperature and its homogenization requires a long time.However, a homogeneous and solid-state synthesis can be carried out in a short time using mechanical alloying, because the volatilization of the constituent elements is inhibited and the subsequent heat treatment is not necessary.In this study, Zn-doped Cu 12-x Zn x Sb 4 S 13 tetrahedrites were prepared by mechanical alloying (MA) and hot pressing (HP), and their electronic transport and thermoelectric properties were examined.A single tetrahedrite phase was successfully obtained by the MA-HP process without subsequent heat treatment.The lattice constant increased with the Zn content, confirming that Zn was substituted for Cu.Zn doping led to p-type conduction characteristics; however, it did not effectively increase the power factor.However, the thermal conductivity showed a marked decrease upon Zn doping, due to decrease in carrier contribution.A dimensionless figure of merit of 0.76 was obtained at 723 K for Cu 11.6 Zn 0.4 Sb 4 S 13 .
Source: 대한금속재료학회지
Authors: Sung-Gyu Kwak, Go-Eun Lee, Il-Ho Kim
Institution: Korea National University of Transportation
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: diamond
Award: G7095636088
OpenAlex ID: W2944563474