Mechanism of Contact Electrification

Contact electrification has been a well-known phenomenon since B.C. 300. However, the origin of triboelectric charge and the charge transfer mechanism are not well understood. To date, the thermionic emission model, Schottky model, flexoelectric model, and intermolecular force model have been proposed for the contact electrification in conductors, semiconductors, and insulators. This article briefly introduces several important research results on the simple-seeming, but baffling, topic of contact electrification.

Electrical properties of composites based on nanoporous carbon material

In this work, the morphological and electrical properties of the composite nanoporous carbon material/thermally expanded graphite or acetylene black have been investigated. Nanoporous carbon material was obtained from plant materials by its thermochemical activation based on potassium hydroxide. The dependence of the specific capacity of the nanoporous carbon/electrolyte electrochemical system on the applied potential was determined by the impedance spectroscopy method. Furthermore, the concentration of charge transfer and the density of states, as well as the flat-band potential of the system under research, were determined based on the Mott-Schottky model.

Electrochemical Study of Anodized Titanium in Phosphoric Acid

The anodization of the Ti-Cu (2%) alloy was carried out in a 5M H3PO4 solution for 2 minutes. The obtained layers are characterized by XPS, X-ray diffraction, and Raman spectroscopy. The results showed that the obtained films are composed of poorly crystallized TiO2 oxide. Electrochemical Impedance spectroscopy studies revealed that the thickness of the formed film increases with increasing anodization potential. Additionally, the resistance of charge transfer becomes higher when the anodization potential increases. Thus, the Mott Schottky model revealed that the formed film is an n-type semiconductor. The density of charge carriers is in good agreement with those found in the literature. Also, it is found that the flat-band potential increases with increasing treatment potential.