Electrostatic Self‐Assembly of Polystyrene Microspheres by Using Chemically Directed Contact Electrification

McCarty, Logan S.; Winkleman, Adam; Whitesides, George M.

doi:10.1002/anie.200602914

Cited by 78 publications

(63 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…3,7 For example, ions are transferred during contact electrification when one solid surface is coated with a layer composed of covalently bound, immobile ionic groups and mobile counterions. 8,9 Here, the mobile counterions are clearly the species transferred from one surface to another after contact. It is, therefore, probable that this mechanism applies generally to contact electrification of any type of insulating materials.…”

Section: ■ Introductionmentioning

confidence: 97%

Charging of Multiple Interacting Particles by Contact Electrification

et al. 2014

View full text Add to dashboard Cite

Many processes involve the movement of a disordered collection of small particles (e.g., powders, grain, dust, and granular foods). These particles move chaotically, interact randomly among themselves, and gain electrical charge by contact electrification. Understanding the mechanisms of contact electrification of multiple interacting particles has been challenging, in part due to the complex movement and interactions of the particles. To examine the processes contributing to contact electrification at the level of single particles, a system was constructed in which an array of millimeter-sized polymeric beads of different materials were agitated on a dish. The dish was filled almost completely with beads, such that beads did not exchange positions. At the same time, during agitation, there was sufficient space for collisions with neighboring beads. The charge of the beads was measured individually after agitation. Results of systematic variations in the organization and composition of the interacting beads showed that three mechanisms determined the steady-state charge of the beads: (i) contact electrification (charging of beads of different materials), (ii) contact de-electrification (discharging of beads of the same charge polarity to the atmosphere), and (iii) a long-range influence across beads not in contact with one another (occurring, plausibly, by diffusion of charge from a bead with a higher charge to a bead with a lower charge of the same polarity).

show abstract

Section: ■ Introductionmentioning

confidence: 97%

Charging of Multiple Interacting Particles by Contact Electrification

et al. 2014

View full text Add to dashboard Cite

show abstract

“…For metals, it is generally accepted that the charge transfer proceeds by electron transfer from the metal with the lower work function to the metal with the higher work function; experiments have shown that the direction of charge transfer between a range of different metals correspond to this trend (Harper, 1967;Lowell and Rose-Innes, 1980). For ionomers with strongly-bound ions of one polarity balanced by loosely-bound ions of the other polarity, systematic studies have shown that triboelectric charging occurs by transfer of the loosely-bound ions (Mizes et al, 1990;Fenzel-Alexander et al, 1994;McCarty et al, 2007).…”

Section: Triboelectric Chargingmentioning

confidence: 90%

Triboelectric charging in single-component particle systems

Lacks

Sankaran

2015

Particulate Science and Technology

View full text Add to dashboard Cite

Particulate systems are prone to electrostatic charging which has important implications on a number of technological areas and natural occurrences. The charging of particles in both of these contexts is the result of an age-old phenomenon known as triboelectric charging that describes the transfer of charged species between material surfaces due to contact or rubbing. In comparison to bulk materials, particle systems are characterized by several unique aspects that make this area of study particularly challenging including their inherently large surface to volume ratios which make them more susceptible to charging and their low mass which can lead to their lifting when electric forces exceed gravitational forces. Perhaps most curious is the universal observation of charge segregation for particles of the same material where there is no clear driving force for charge transfer. In this review, we present a summary of key issues and recent progress relating to triboelectric charging of particle systems, including potential mechanisms for charge transfer, how collision dynamics plays a role, and theoretical and experimental support for charge segregation.

show abstract

“…6,9 In particular, for two solid surfaces covered with covalently bound, fixed, ionic functional groups and mobile counterions, it is clear that charge separation results from the transfer of mobile counterions between the surfaces. [10][11][12] For example, polystyrene surfaces that are chemically modified with sulfonic (or quaternary amine) groups charge negatively (or positively) when brought into contact with polyethylene -an observation that is in accordance to the ion-transfer mechanism. In a similar demonstration, polymers that contain bonded cations acquire a positive charge, whereas polymers that contain bonded anions acquire a negative charge, during contact electrification.…”

mentioning

confidence: 90%

“…Experimentally, the charge developed on the surface during contact electrification has the same polarity as that of the polyelectrolyte on the outermost layer; this observation is consistent with the ion-transfer mechanism for contact electrification. 6,[10][11][12] The absolute magnitude of the rate of charging is different for PDDA-and PSS-terminated films; this difference may be due to a faster rate of transfer of Cl -ions than Na + ions from the substrate to the rolling sphere. We cannot, however, rule out contributions from other ions (e.g., hypothetically hydroxide or hydronium).…”

mentioning

confidence: 99%

Layer-by-layer films for tunable and rewritable control of contact electrification

Soh¹,

Chen²,

Vella³

et al. 2013

Soft Matter

View full text Add to dashboard Cite

Charges generated by contact of solid surfaces (contact electrification) can be hazardous or useful depending on the circumstance. This paper describes a process to design a solid surface rationally to either induce or prevent charging during contact electrification; this process coats the surface with polyelectrolytes. It is observed experimentally that a surface coated with a layer of a polymer having multiple, covalently attached positive charges (a "polycation") develops a positive charge after contacting another surface; a surface coated with a layer of polymer having negative charges (a "polyanion") develops a negative charge. By coating the surface using layerby-layer (LBL) deposition, the tendency of the surface to charge either positively or negatively can be switched: adding a layer of polyelectrolyte with charge opposite to the charge on the surface switches the polarity of the surface. Through microcontact printing (µCP), the surface can be stamped to create a mosaic pattern of polycation and polyanion -and importantly, the fraction of the surface area covered with polycation and polyanion can be tuned by using stamps of different patterns. Using poly(diallyldimethylammonium chloride) (PDDA) as the polycation and poly(sodium 4-styrenesulfonate) (PSS) as the polyanion, it is found that for a surface with >75% PSS, the surface charges negatively; with <75% PSS, the surface charges positively. At ~75% PSS, the surface becomes non-charging. The patterns on the surface can, subsequently, be erased through coating the surface with a uniform layer of polyelectrolyte. After erasing, the surface is rewritable by depositing or patterning the surface with a desired polyelectrolyte.

show abstract

Electrostatic Self‐Assembly of Polystyrene Microspheres by Using Chemically Directed Contact Electrification

Cited by 78 publications

References 17 publications

Charging of Multiple Interacting Particles by Contact Electrification

Charging of Multiple Interacting Particles by Contact Electrification

Triboelectric charging in single-component particle systems

Layer-by-layer films for tunable and rewritable control of contact electrification

Contact Info

Product

Resources

About