Interfacial Nanostructures and Photoelectric Properties in Self-Assembled Cholesterol Amide Derivative Langmuir–Blodgett Films

Abstract

Cholesterol is widely used in the field of amphiphilic self-assembly as a small organic molecular structural unit. In this article, new cholesterol amide derivative (CHAM) films via molecular self-assembly technology have been successfully prepared. Scanning electron microscope, transmission electron microscope, UV–Vis spectra, atomic force microscopy (AFM), contact angle and Fourier transform infrared spectroscopy were measured to characterize the morphology and nanostructure of the prepared self-assembled CHAM Langmuir–Blodgett (LB) films. The obtained experimental data revealed that different subphases played an important role in formation of a stable LB film, resulting in different assembly behavior. CHAM contains adamantane units and highly symmetrical tricyclic aliphatic hydrocarbon clusters, so it can combined with cyclodextrin through host–guest interact, for CHAM act as host and cyclodextrin containing a hydrophobic cavity act as guest. The morphology of single-layer Langmuir films with different subphases was characterized by AFM, indicating that the CHAM molecules formed a stable LB films on the surface of the pure water subphase, cyclodextrin subphase and cyclodextrin polymer subphase. The photoelectric properties were characterized by J-V characteristics, EIS response and impedance map, and it was found that the CHAM film had better photoelectric properties.