Thermoelectric Materials and Applicative Issues for Energy Harvesting to Power IoT Sensors and Devices

There is a vital need to develop technologies to dynamically harvest energy from surroundings to power IoT applications [1]. Thermoelectrics is promising, since it enables utilization of ubiquitous thermal energy like body heat [2]. In regards to viable thermoelectric applications, the performance (high Figure of merit ZT) of the materials is important, but likewise critical is the appropriate processing and fabrication methods of effective modules. The cheapness of materials can usually not justify poor thermoelectric performance since the cost of viable materials is typical not the major cost in the module production. Considering applicative issues, we have been developing two strategies, developing inorganic thermoelectric thin films, and developing hybrid or “sticky” inorganic-organic composite materials [3]. The former using sputtering can be compatible to industrial processes and the thin film modules can be readily integrated into IoT devices. The latter can potentially enable roll to roll production of inexpensive large area sheets. I will present our work on these two strategies.