A halogen-bonding foldamer molecular film for selective reagentless anion sensing in water.

We describe self-assembled monolayers of novel halogen-bonding and hydrogen-bonding foldamer receptors capable of selectively recruiting perrhenate, iodide and thiocyanate in water. Unprecedented anion sensing via impedance-derived capacitance spectroscopy enables subsequent sensitive and selective anion detection without the need for a redox probe. Importantly, the sensing of any anion should be possible using this novel electrochemical approach.