• Universitat de València

There are currently commercial thermoelectric cooling devices based on bismuth telluride (Bi2Te3) known as Peltier modules used in refrigeration systems. The use of these devices for large surface applications is completely unfeasible due to their high cost. There are also some prototypes that use n-type and p-type organic semiconductors, arranged alternately. Many of these devices have serious drawbacks, such as their low efficiency and low feasibility in scaling up to large areas. Some thermoelectric conversion devices have also been developed that use a single type of organic semiconductor, using semiconducting polymers, such as PEDOT, PANI, Polypyrrole, etc., with the possibility of incorporating a flexible substrate, in which the semiconducting polymer elements have a vertical conformation. However, the problem with these devices is that it is always necessary to dissipate the heat on the cold side in order to maintain an acceptable temperature difference, which leads to a loss of efficiency. Furthermore, these thermoelectric materials are prepared using mechanical recovery methods, and the manufacturing process is complicated because it involves numerous stages, which results in a considerable increase in the cost of the device. It is necessary to offer an alternative to the state of the art that covers the shortcomings found in this one, providing a thermoelectric device that, among other things, improves the efficiency of the known ones, allows to keep the cold and hot parts far enough apart so as not to have the need to dissipate the heat from the cold part, and is suitable for large-scale applications.

Researchers at the Universitat de València have developed a new organic thermoelectric device composed of a completely flexible semiconductor polymer, for the production of energy in applications on large surfaces, such as building walls and ceilings or solar panels. The device is based on thermoelectric unions of organic semiconductors (PEDOT, PANI, Polypyrrole, etc...), with conductive polymers of only one type of carrier (p-type or n-type). Its novelty lies in the planar geometry and in the manufacture of the thermoelectric pots of the device, which are all manufactured at the same time, which allows it to be energy efficient, and the economical large-scale manufacture.

Various energy and electronics sectors. Energy production (from heat). Refrigeration. Construction of intelligent buildings.

The main advantages provided by the invention are:

• Large-scale applications (building fronts, façades, energy supplementation in solar panels, etc.).
• Allows manufacturing in multiple geometries.
• Absence of toxicity.
• Due to its flexibility, it can be easily implemented in its final application.

• Patent granted