Electrical Properties of Molten CuCl-Cu2Te Mixtures

The electrical conductivity sigma and the thermoelectric power S of molten (CuCl)(1-c)(Cu2Te)(c) mixtures are measured as a function of composition and temperature. The electrical conductivity of the mixtures decreases rapidly with the addition of CuCl to liquid Cu2Te. The thermoelectric power of molten (CuCl)(1-c)(Cu2Te)(c) mixtures shows a smooth increase with increasing composition of CuCl. The experimental results suggest that the dominant transport process in the molten (CuCl)(1-c)(Cu2Te)(c) mixtures changes from electronic conduction to ionic conduction. The composition dependences of sigma and S were analyzed using the fundamental equation of electrical current densities due to electrons and ions. According to this analysis, the conductivity gap increases gradually upon the addition of CuCl to liquid Cu2Te and the conductivity gap is about 0.55 eV for molten (CuCl)(0.4)(Cu2Te)(0.6) mixture.