Triboelectric nanogenerators

TENGs

Triboelectric nanogenerators (TENGs) are a new type of electricity production device, which converts ambient energy like kinetic energy from wind or vibrational energy from sound into electricity. The mechanism is based the spontaneous generation of electrostatic charge when two chemically different materials come into contact (contact electrification) – the tribonegative material accepts electrons which the tribopositive material donates. The separation of the two materials induces an electrical current in an external circuit, which can be used to power appliances.

The TENG working principle

Sustainable TENGs

  • Algae
  • Cellulose
  • Clay
  • Biomass
Sustainable rawmaterials for TENGs

While TENGs produce sustainable energy, the TENGs themselves are generally not made from sustainable, that is renewable, materials. Therefore, one research line within FOAMIFY is to develop sustainable TENGs constructed from renewable or abundant materials resources. Examples are biopolymers (cellulose, alginate, chitosan) and clay minerals amongst others.

Hybrid TENGs

Classical TENGs convert one mechanical energy source into electricity. That may be the periodic motion induced by wind, waves, sound, falling rain drops or footsteps. Yet, we are surrounded by more ambient energy sources, like heat or light. Each source can be harvested with a nanogenerator of its one, such as thermoelectric and pyroelectic nanogenerators in the former case and photovoltaic cells in the latter case. Now, the different types of nanogenerators and cells can be combined in one hybrid nanogenerator harvesting at the same time different energy sources and increasing this way the efficiency, versatility and effectiveness. Within FOAMIFY, hybrid TENGs will be developed from a combination of tribo- and piezoelectric nanogenerators and tribo- and thermoelectric nanogenerators.

Porous TENGs

It has been shown that porous materials can enhance the electrical output of TENGs. The reason is that pores at and close to the surface increase the area for charge to build up. This leads to more electrostatic charge and in turn to higher electrical currents provided by porous TENGs. At the same time, pores are an essential part of insulation materials, which creates a synergy between TENGs and insulation foam materials.