Triboelectrinen

The triboelectric effect, or triboelectric charging, is the generation of electric charge on insulating materials as a result of contact and subsequent separation between two different materials. When surfaces touch and then part, electrons may transfer from one material to the other, leaving one surface negatively charged and the other positively charged. The exact mechanism can involve electron transfer, ion transfer, or transfer of material fragments, and it is influenced by surface conditions, contamination, and environmental factors such as humidity.

Materials can be placed in a triboelectric series according to their tendency to gain or lose electrons, but the ordering is not universal and depends on factors like material form, surface finish, and atmosphere. Humidity tends to reduce static charges by allowing charge dissipation through a thin moisture layer.

The magnitude of produced charge is often described by surface charge density or potential difference and depends on contact area, pressure, duration of contact, and separation speed. Surface roughness, contamination, and adsorbed films also affect charging behavior.

Applications include energy harvesting with triboelectric nanogenerators (TENGs), electrostatic separation, and xerography, as well as self-powered sensors and actuators. The triboelectric effect is studied within the fields of tribology and electrostatics.

Historically, the effect has been observed since antiquity with amber and other materials; the term triboelectric derives from friction (tribos) and electricity. Modern research emphasizes how material properties, nano-scale surface features, and environmental conditions govern charge generation.