A smart surface with switchable wettability by an ionic liquid

Abstract

Smart control of surface wettability by ionic liquids (ILs) is significant for designing IL-related intelligent materials and devices. Herein, we present mixed molecular brushes comprised of poly(phenylethyl methacrylate) and 1H,1H,2H,2H-perfluorodecyltrimethoxysilane (PPhEtMA-co-PFDMS) grafted surfaces that are capable of dynamically regulating 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIm][NTf₂]) wettability. ¹H NMR and quartz crystal microbalance characterization demonstrate that the wettability changes result from a temperature-dominated cation–π interaction between [EMIm][NTf₂] and PPhEtMA-co-PFDMS brushes.