Preparation of N-type Silicon Carbide-Based Thermoelectric Materials by Spark Plasma Sintering

The SiC/Si3N4 sintered materials were prepared by Spark Plasma Sintering at 2000°C. The crystal structure of sintered materials is cubic β-SiC type with relative density higher than 80%. All sintered materials show n-type conduction and the carrier concentration increases with increasing Si3N4 concentration. Seebeck coefficient α and electrical conductivity σ increased with increasing temperature indicating suitable for high temperature thermoelectric conversion. Thermoelectric properties are improved by addition of Si3N4 and the power factor α2σ takes a maximum value at SiC–7 mass%Si3N4.