Synthesis and thermoelectric properties of polyaniline

Abstract

Electrical conductivity and seebeck coefficient at different temperatures, and thermal conductivity at room temperature for various doped polyaniline (PAn) samples were measured, and the thermoelectric figure of merit ZT was calculated. The effects of preparation methods and temperature on thermoelectric properties were discussed. The results show that the electrical conductivity and the seebeck coefficient of PAn are strongly dependent on the preparation conditions and temperature. The electrical conductivity becomes larger and the seebeck coefficient becomes smaller as PAn molecular weight increase. Redoping by organic acid and HCl results in an increase in both electrical conductivity and Seebeck coefficient of PAn, and therefore ZT value. The electrical conductivity increases and the seebeck coefficient decreases as the temperature increases when T<T_d (dedoping temperature). The decreasing of the electrical conductivity and increasing of the seebeck coefficent take place by dedoping when T>T_d. The thermal conductivity is lower, and insensitive to the sample preparation conditions.