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arXiv · cond-mat/0605058

Colloidal Electrostatic Interactions Near a Conducting Surface

Marco Polin·David G. Grier·Yilong Han
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Abstract

Charge-stabilized colloidal spheres dispersed in deionized water are supposed to repel each other. Instead, artifact-corrected video microscopy measurements reveal an anomalous long-ranged like-charge attraction in the interparticle pair potential when the spheres are confined to a layer by even a single charged glass surface. These attractions can be masked by electrostatic repulsions at low ionic strengths. Coating the bounding surfaces with a conducting gold layer suppresses the attraction. These observations suggest a possible mechanism for confinement-induced attractions.

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Marco Polin, David G. Grier, Yilong Han. 2006-05-02. Colloidal Electrostatic Interactions Near a Conducting Surface. https://doi.org/10.1103/physreve.76.041406

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