Thermoelectric properties of sintered SiC/Si/Ag thermoelectric semiconductor

Silicon carbide is a wide gap semiconductor which is expected to be used in the high temperature region. It has large electrical resistivity and large thermal conductivity. These properties are not favorable for thermoelectric devices. In this paper, Si and Ag were selected as dopants to reduce the thermal conductivity and the electrical resistivity, respectively. These dopants were effective in improving the thermoelectric properties in our previous works. The thermoelectric properties of SiC/Si/Ag have been studied over temperatures ranging from room temperature to 750°C as a function of both Si concentration (10.0 wt.%~40.0 wt.%) and Ag concentration (1.0 wt.%~4.0 wt.%). The thermal conductivity and the electrical resistivity decreased with increasing temperature. The figure of merit Z approached 1.1×10^-4 K^-1 at around 750°C. We conclude that Si with Ag doped SiC is a promising thermoelectric material