Preparation of C3F7-azo+/LaNb2O7− intercalated nanocomposite by ion-exchange method and its application as electrochemical sensors

Abstract

Using the excellent ion-exchange property and unique lamellar structure of lanthanum niobate KLaNb2O7, trans-[2-(2,2,3,3,4,4,4-heptafluorobutylamino) ethyl]-{2-[4-(4-hexyphenylazo) -phenoxy] ethyl}-dimethylammonium (abbreviated as C3F7-azo+Br−) was inserted into LaNb2O7− lamellar plate by ion-exchange method, and C3F7-azo+/LaNb2O7− nanocomposite was synthesized for the first time.X-ray diffraction (XRD), Fourier transform infrared spectrometer (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy disperse spectroscopy (EDS) were used to characterize the prepared materials. Differential pulse voltammetry (DPV), cyclic voltammetry (CV) and electrochemical impedance spectrum (EIS) were used to detect and verify the electrochemical performance of C3F7-azo+/LaNb2O7− nanocomposite modified glassy carbon electrode (C3F7-azo+/LaNb2O7−/GCE) for simultaneous detection of dopamine (DA) and ascorbic acid (AA). The results showed that the detection limit of C3F7-azo+/LaNb2O7−/GCE in N2 saturated PBS (pH = 5.0, 0.1 M) was 0.57 μM for AA and 0.61 μM for DA in the range of 5.0 to 77.0 μM. It is concluded that C3F7-azo+/LaNb2O7− nanocomposite has excellent electrochemical performance and can be utilized in detecting AA and DA simultaneously.