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arXiv · 1801.05635

Controlling polyelectrolyte adsorption onto carbon nanotubes by tuning ion-image interactions

Alpha A. Lee·Sarah V. Kostinski·Michael P. Brenner
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Abstract

Understanding and controlling polyelectrolyte adsorption onto carbon nanotubes is a fundamen- tal challenge in nanotechology. Polyelectrolytes have been shown to stabilise nanotube suspensions through adsorbing onto the nanotube surface, and polyelectrolyte-coated nanotubes are emerging as building blocks for complex and addressable self-assembly. The conventional wisdom suggests that polyelectrolyte adsorption onto nanotubes is driven by specific chemical or van der Waals interac- tions. We develop a simple mean-field model and show that ion-image attraction is a significant effect for adsorption onto conducting nanotubes at low salt concentrations. Our theory suggests a simple strategy to selectively and reversibly functionalize carbon nanotubes based on their electronic structure which in turn modifies the ion-image attraction.

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Alpha A. Lee, Sarah V. Kostinski, Michael P. Brenner. 2018-01-17. Controlling polyelectrolyte adsorption onto carbon nanotubes by tuning ion-image interactions. https://doi.org/10.1021/acs.jpcb.7b11398

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