The role of bulk traps in metal-insulator contact charging

Abstract

Metal-insulator contact charging models are presented for insulators having (a) traps uniformly distributed in the energy gap and (b) discrete traps in the energy gap. It is shown that in the former case the relationship between the magnitude of the charge transferred and the workfunction difference is linear, while in the latter case it ranges from an exponential to a quadratic depending on the band bending and the energetic position of the traps. Screening lengths are calculated for the two cases, and it is shown that the thickness of the insulator is usually not the limiting factor in contact charging, even for thin-film insulators. Finally, it is shown that the times required for the charge transfer can be short.

Temperature Effect on Performance of Triboelectric Nanogenerator

“…www.advancedsciencenews.com www.aem-journal.com contact electrification is given by Chowdry and Westgate, [36] …”

“…The electrical output of TENG as a function of e r and N t is shown in Figure 4d. [36] We suppose the effect of temperature perturbation would decline the stability of charges so that the magnitude of charges on the PTFE thin layer of surface would be reduced base on the theoretical calculations. The triboelectric charges on the PTFE just are generated on the several hundred nanometers thin layer of the PTFE surface during a process of contact/friction electrification.…”

The charging of microparticles in corona discharge in the air

“…Перенос заряда происходит достаточно быстро [6] (порядка нескольких микросекунд) посредством туннелирования электронов между проводником и поверх-ностными состояниями в диэлектрике в непосредственной близости от точки контакта. Поверхностные состояния действуют как «ловушки» и обеспечивают накопление элек-тронов [7]. Обратное туннелирование пренебрежимо мало, если поверхность имеет не очень большой заряд [8].…”

The impact of electrostatic charge in pharmaceutical powders with specific focus on inhalation-powders

“…In the charging process of the metalinsulator category, three different proceedings can be distinguished (Matsusaka & Masuda, 2003). These are electron transfer, where the charging occurs by a flow of electrons (Chowdry & Westgate, 1974), ion transfer, where ions are exchanged by diffusion (Diaz & Fenzel-Alexander, 1993;Guay, Ayala, Diaz, & Dao, 1991;Harper, 1967;Robins, Lowell, & Rose-Innes, 1980) and material transfer, where material is rubbed off one contacting body and adheres on the other one (Tanoue, Ema, & Masuda, 1999). Normally the charging process is a combination of these three proceedings.…”