Direct electrodeposition of cationic pillar[6]arene-modified graphene oxide composite films and their host-guest inclusions for enhanced electrochemical performance.

In the present work, electrochemically reduced graphene oxide-cationic pillar[6]arene (ErGO-CP6) composite films on glassy carbon electrodes (GCEs) were prepared directly from graphene oxide-cationic pillar[6]arene (GO-CP6) dispersions by a facile one-step pulsed electrodeposition technique. The preparation of GO-CP6 and its subsequent electrochemical reduction were confirmed by Fourier transform infrared (FTIR) spectroscopy, UV-vis spectroscopy (UV-vis), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), zeta potential, Raman spectroscopy, and scanning electron microscopy (SEM). SEM result reveals that ErGO-CP6 could form a homogeneous film when GO-CP6 was electrodeposited on the surface of a GCE. Furthermore, Raman and XPS results confirm the removal of oxygen-containing functional groups present on the GO-CP6 surface after electrochemical reduction. Electrochemical results reveal that ErGO-CP6 films could show much higher electrochemical response to theophylline (TP), ascorbic acid (AA), acetaminophen (APAP), and folic acid (FA) than unmodified ErGO films and bare GCE, which is considered to be the synergistic effect of the graphene (excellent electrical properties and large surface area) and CP6 molecules (high inclusion complexation and enrichment capability).