Preparation of unique PEDOTnanorods with a couple of cuspate tips by reverse interfacial polymerization and their electrocatalytic application to detect nitrite

Abstract

By using Ce(SO₄)₂·4H₂O as an oxidant and sodium bis(2-ethylhexyl) sulfosuccinate (AOT) as a surfactant, unique poly(3,4-ethylenedioxythiophene) (PEDOT) nanorods with a couple of cuspate tips were successfully prepared by reverse interfacial polymerization. The morphology of these PEDOT nanorods was very regular and well-dispersed with widths and lengths from one tip to another tip mostly in the range 40–60 nm and 370–460 nm, respectively. The chemical structure and formation mechanism of PEDOT nanorods are discussed in detail by several analysis methods. AOT played an important role during the formation of PEDOT nanorods. It could be combined with Ce⁴⁺ to form a unique template for the polymerization of 3,4-ethylenedioxythiophene (EDOT) in the cylindrical micelles formed by n-hexane, H₂O and AOT. Furthermore, the application of PEDOT nanorod-modified glassy carbon electrode (GCE) as an electrochemical sensor for detecting nitrite was also investigated. Due to their good dispersibility and large surface area, PEDOT nanorods exhibited good linearity and sensitivity of cyclic voltammetry (CV) responses as well as amperometric responses for electrocatalytic oxidation of nitrite. It resulted in PEDOT nanorods acting as a good steady and sensitive electrode material for detecting nitrite.