Enhancement of thermoelectric efficiency of doped PCDTBT polymer films

Abstract

Conjugated polymers may be used as thermoelectric materials due to their low thermal conductivity and have the advantageous characteristics of conventional polymers, such as low weight, non-toxicity and low cost. Here, a detailed investigation into the thermoelectric properties of PCDTBT films is reported. Moreover, in order to improve the thermoelectric properties of this polymer, FeCl₃ is used as a doping agent. For the most optimally doped film reported in this work, a power factor value of 24 μW m⁻¹ K⁻² is obtained at 150 °C. The different films were characterized by wide-angle X-ray scattering (WAXS) experiments at different temperatures. In order to see the temperature effect, the thermoelectric power factor is measured as a function of temperature from (from RT to 150 °C). Thermal conductivity at room temperature is calculated with two independent methods which give values in agreement within the margin of uncertainty. The results obtained show promise and give insight to motivate future investigation into these types of carbazole derivates.