Photoinduced p‐ to n‐type Switching in Thermoelectric Polymer‐Carbon Nanotube Composites

Thermoelectric plastics: from design to synthesis, processing and structure–property relationships

“…11,14,36,42 For instance, Dörling et al measured a bulk thermal conductivity of 0.55 W m –1 K –1 for one millimetre-thick pellets of a P3HT:MWNT nanocomposite with a filler content of 80 wt%, which was only slightly higher than the value of 0.29 W m –1 K –1 measured for neat P3HT. 42 However, care should be taken when evaluating the thermal conductivity of thin samples since the high aspect ratio of carbon nanotubes is likely to lead to in-plane alignment and thus anisotropic electrical and thermal conductivities.…”

“…Air-stable n-type behaviour can also be achieved by incorporating nitrogen into carbon nanotubes during synthesis (Table 1). 42 …”

Influence of crystallinity on the thermoelectric power factor of P3HT vapour-doped with F4TCNQ

“…

Doping of the conjugated polymer poly(3-hexylthiophene) (P3HT) with the p-dopant 2, 3,5,7,8, is a widely used model system for organic thermoelectrics.We here study how the crystalline order influences the Seebeck coefficient of P3HT films doped with F4TCNQ from the vapour phase, which leads to a similar number of F4TCNQ anions and hence (bound + mobile) charge carriers of about 2 Â 10 À4 mol cm

À3. We find that the Seebeck coefficient first slightly increases with the degree of order, but then again decreases for the most crystalline P3HT films.

…”

Review—Towards the Next Generation of Thermoelectric Materials: Tailoring Electronic and Phononic Properties of Nanomaterials

“…20 Finally, under UV illumination the p-to n-type behavior can also be changed (See Figure 3a, where a scheme of the device-fabrication based change in the Seebeck coefficient from positive values (p-type) to negative values (n-type) under UV illumination is shown). These concepts were implemented in a proof of concept flexible organic thermoelectric generator 20 (See Figures 3b and 3c). Also, a semi-empirical phenomenological model has been developed to understand the thermal transport properties of these P3HT/CNTs composites, which will be discussed in Polymeric materials section.…”