Self-assembly behavior of layered titanium niobate and methylene blue cation and electrochemical detection of dopamine

A novel nanocomposite MB / Ti 5 NbO 14 was successfully synthesized by exfoliation / restacking method. The structure and morphology were characterized by X-ray powder diffraction (XRD), energy-dispersive spectroscopy (EDS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet–visible spectroscopy (UV–vis), and Fourier transform infrared (FTIR). It is indicated that materials were successfully synthesized, and MB was successfully intercalated between the layers of [Ti 5 NbO 14 ] 3− forming a layer with its molecular plane inclined to [Ti 5 NbO 14 ] 3− layer at about 39.88°. Meanwhile, electrochemical measurement demonstrated that MB/Ti 5 NbO 14 nanocomposite exhibited enhanced electrochemical activities towards the oxidation of dopamine due to increased electro-transport properties. And the MB / Ti 5 NbO 14 modified electrode has a detection limit of 2.01 µM ( R/N 3.0) with the concentration range from 0.0249 to 0.4988 mM. This study indicated that this electrochemical sensor has satisfactory stability, and detects dopamine with strong anti-interference performance, repeatability, and reproducibility. Graphic abstract