Chirality-Driven Adhesion: Enantioselectivity at the Surface of Fluorous Binaphthyl Amphiphile Films.

Abstract

Enantioselective adhesion is a highly sought-after property in advanced materials, with potential applications in chiral sensing, smart robotics, and enantiomeric separation. Chiral films with uniform morphology and well-tunable chirality can serve as excellent platforms for macroscale enantioselective adhesion, yet their facile fabrication remains challenging. In this study, we developed a new class of axially chiral fluoroalkylated amphiphiles and prepared uniform, optically transparent chiral films through a straightforward drop-casting technique. These films exhibit remarkable enantioselective adhesion properties. Homochiral films demonstrate strong interfacial adhesion and can withstand a weight of up to 3 kg per 0.2 mg·cm^-2 of film, whereas heterochiral or racemic pairings show minimal adhesion. The enantioselectivity was further validated through macroscopic adhesion experiments and atomic force microscopy. Mechanistic studies indicate that fluorinated solvents regulate molecular orientation through affinity differences toward different moieties of amphiphilic molecules, exposing the naphthalene ring on the film surface. During the adhesion process, the chiral binaphthyl structure accomplishes chiral recognition through spatial configuration matching. This work presents the first demonstration of macroscopic visualization of chiral interactions through adhesive behavior, opening new avenues for chiral sensing, enantiomeric separation, and the rational design of chiral functional materials.