Thermoelectric properties of Cu2Ga4Te7 based compounds with Zn substitution for Cu and Ga.

We present two series of Cu2Ga4Te7-based compounds with Zn substituting for Cu (Cu-poor) and Ga (Ga-poor), and have observed enhanced thermoelectric performance. Generally, the Seebeck coefficient ( α) and lattice thermal conductivity ( κL) increase and electrical conductivity ( σ) decreases with the Zn content increasing. The variation in electrical properties might be mainly due to the formation of antisite defects ( [ABSTRACT FROM AUTHOR]