Temperature dependence of nylon and PTFE triboelectrification

Abstract

Contact electrification, or tribocharging, is pertinent to a broad range of industrial and natural processes involving dielectric materials. However, the basic mechanism by which charge is transferred between insulators is still unclear. Here, we use a simple apparatus that brings two macroscopic surfaces into repeated contact and measures the charge on the surfaces after each contact. We vary the temperature of the surfaces, and find that increasing temperature leads to a decrease in the magnitude of charge transfer. When paired with a Monte-Carlo simulation and TGA measurements, our results support a mechanism where adsorbed surface water is crucial for charge exchange. Our setup is easily extendable to a variety of industrially relevant materials.

Precision measurement of tribocharging in acoustically levitated sub-millimeter grains

“…Throughout each collision-series, the total charge of the particles is conserved within experimental error, in line with previous findings 11 that levitated particles exchange charge only during collisions (the particles do not exchange charge with the ambient gas). In addition, the lack of charge saturation implies that our particles contact each other at slightly different spots each time, in agreement with previously reported trends 11,18 . Based on these two observations, we can infer an average surface charge density.…”

“…Several candidates for the charge carrying species have been suggested, including electrons in trapped surface states [14][15][16] , ions in atomically thin water layers 11,17,18 , and mechanoradicals produced during contact 19,20 . Elucidating the fundamental mechanism of collisional charging between grains thus calls for systematic, quantitative experiments.…”

Quantitatively consistent scale-spanning model for same-material tribocharging

“…There is some indication that uniform in-plane strain during compression could play a role [31], but this does not explain statistical fluctuations in localized strain at a particular mesoscopic length scale. A second, widely held view makes connections to 'islands' of adsorbed surface water [17,18,37,39,40], which definitively do form on surfaces with a similar size scale to charge mosaics [41]. To add to this idea, Burgo et al showed that water causes virtually all materials it touches to charge negatively [42]-hence patches of 'wet' surface vs 'dry' surface might be interpreted as donor/acceptor regions.…”

Single-Electrode Electrochemistry: Chemically Engineering Surface Adhesion and Hardness To Maximize Redox Work Extracted from Tribocharged Silicon

“…The first hypothesis is therefore that of a link between tribocharging and material transfer -as opposed to electron transfer 8 -with the positive charge on the silicon indicating a transfer of fragments from PVC to silicon. Notably, surface water is known to play a crucial role in the electrification of dielectrics, 4,[23][24][25] and acetylene-terminated monolayers have a great ability to rapidly adsorb water. 26 Measurements of the static charges developed on a-Si samples (with and without monolayers) rubbed against PVC inside a glove box, under argon atmosphere with water levels below 0.3 ppm, showed consistently lower Coulombs readings than in air (Figure S7, Supporting Information).…”