[Back]

K. Cui, K. Mali, O. Ivasenko, D. Wu, X. Feng, M. Walter, K. Müllen, S. De Feyter, S. Mertens:
"Squeezing, Then Stacking: From Breathing Pores to Three-Dimensional Ionic Self-Assembly under Electrochemical Control";
Angewandte Chemie - International Edition, 53 (2014), 12951 - 12954.

We demonstrate the spontaneous and reversible
transition between the two- and three-dimensional self-assembly
of a supramolecular system at the solid-liquid interface
under electrochemical conditions, using in situ scanning
tunneling microscopy. By tuning the interfacial potential, we
can selectively organize our target molecules in an open porous
pattern, fill these pores to form an auto-host-guest structure, or
stack the building blocks in a stratified bilayer. Using a simple
electrostatic model, we rationalize which charge density is
required to enable bilayer formation, and conversely, which
molecular size/charge ratio is necessary in the design of new
building blocks. Our results may lead to a new class of
electrochemically controlled dynamic host-guest systems,
artificial receptors, and smart materials.