Powder Technology, Vol.383, 292-301, 2021
A detailed study of the interaction between levitated microspheres and the target electrode in a strong electric fi eld
In this work, we report on an in-depth study of how 10 mu m silica and polystyrene particles interact with a target electrode after they were levitated by applying a strong electric field. The results show that, under these condi-tions, silica particles unexpectedly have a higher tendency to adhere on a fluorocarbon coated electrode com-pared to a bare, non-coated silicon electrode. Relative adherence ratios gamma up to gamma = 4.7 were observed. Using the colloidal probe technique, atomic force microscopy (AFM) and Kelvin probe force microscopy (KPFM), the observations can be explained by a mechanism where particles dissipate their energy through adhesive forces combined with permanent surface deformations during impact and charge transfer through the contact electri-fication phenomenon. All these processes attribute to increasing the probability that levitated particles attain ve-locities that are lower than the sticking velocity. (c) 2021 Elsevier B.V. All rights reserved.