Surface characterization of bis-amide calix[4]arene doped SWCNT nanocomposite and its application as an electrochemical sensor for the determination of Al3+ ion

Abstract

This study focuses on the optical, wettability, morphological and sensing properties of the chromogenic bis-amide calix[4]arene-SWCNT nanocomposite thin film. Nanocomposite solution was done by mixing single-walled carbon nanotubes with 5,17-bis(phenylazo)-26,28 bis{[(ethoxycarbonyl)methylcarbamoyl] methoxy}-25,27-di(ethoxycarbonylmethoxy)-calix[4]arene in chlorobenzene. The possible interactions between bis-amide calixarene and SWCNT that may be responsible for enhancement in certain properties of the nanocomposite were highlighted. Firstly, the surface of the modified electrode was characterized by using UV–visible spectrophotometer and contact angle measurement (CAM). The effect of the SWCNT loading in the solution and the heating process on the film properties plays a crucial role in the optical and wettability properties of the CNTs based films. Then, morphological study was examined before and after CNT incorporation by using scanning electron microscopy. Finally, the sensing properties of bis-amide calix[4]arene-SWCNT thin film coated gold electrode were investigated using electrochemical impedance spectroscopy (EIS) toward the detection of Al³⁺ ion.