The researchers have developed a new process for this purpose: Small molecules are combined to form polymers that can transport negative charge carriers (electrons). The highlight is that, unlike comparable polymers, this polymer is in the liquid state. This enables them to print or spray very thin and smooth organic functional layers on surfaces. The researchers now want to develop thermoelectric generators that supply energy to sensors in places that are difficult to access, for example, where battery replacement is not useful, not possible or very expensive. In particular, the researchers think about warm pipes that do not get hotter than 100 degrees Celsius - which is the upper limit for the polymers investigated so far. There are plenty of applications on the Internet of Things: sensors and electronic devices could use these thermoelectric generators to cover their own electrical energy requirements.
Thermoelectric generators have been known as a concept for years. However, their efficiency is still far too low for mass use: on average, they convert only 6% of thermal energy into electrical energy. However, if it were possible to significantly increase the yield, this could have far-reaching consequences for energy balances: Car manufacturers, for example, have long dreamed of coating their engines with such thermoelectric generators in order to electrically recycle the waste heat from the drive units, which had previously been painstakingly cooled away. According to estimates, the fuel consumption of cars could be reduced by up to a tenth. However, the solutions tested to date are not very effective.