Details

Autor(en) / Beteiligte

• Gustiani, V F
• Septiany, L
• Nugroho, A A
• Blake, G R

Titel

Thermoelectric Performance of Ge 0.99-x Na 0.01 Ag x Se

Ist Teil von

• Journal of physics. Conference series, 2019-08, Vol.1245 (1), p.12094

Erscheinungsjahr

2019

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• Abstract Doped GeSe has theoretically been predicted to exhibit ultralow thermal conductivity that yields a high figure of merit (ZT) of 2.6 at 800K. However, experimental studies of the thermoelectric performance of GeSe have received little attention due to poor doping efficiency. Doping GeSe with Na is reported to reduce its thermal conductivity due to the growth of Na-rich precipitates, but the electrical resistivity remains too high. In order to suppress both thermal conductivity and resistivity, a co-doping approach was used by introducing Na and Ag. Characterization using scanning electron microscopy indicates the presence of both Ag- and Na-rich precipitates within the GeSe matrix. The resistivity decreases by ∼6 times at high temperature with increasing Ag concentration. However, the thermal conductivity only decreases by ∼1.5 times after Ag doping of about 0.5%. The Seebeck coefficient remains constant with doping at high temperature. Overall, the thermoelectric performance of Na,Ag co-doped GeSe is optimum at around 0.5 mol% of Ag.