Carbon Nanotube-Based Polymer Composite Thermoelectric Generators

Carbon nanotube-based polymer composites possess several properties that make them ideal for use in low powered waste heat recovery applications not suitable to nonorganic crystalline materials even though their thermoelectric performance is lower, such as their light weight and flexible physical structure. Additionally, the favorable thermoelectric properties of the carbon nanotubes with moderate Seebeck coefficients and potentially large electrical conductivities result in modest power factors, while the low thermal conductivity of the polymer host aids in maintaining a temperature gradient across the composite. In order to effectively utilize a thermoelectric material in a practical application, they must be combined in a thin film device structure consisting of alternating p-type and n-type elements that are connected electrically in series and thermally in parallel. The device performance is then dictated by the intrinsic thermoelectric properties of the individual layers in the device. Ultimately, the total power output is limited by several extrinsic properties of the specific application.