One-pot self-assembly preparation of thiol-functionalized poly(3,4-ethylenedioxythiophene) hollow nanosphere/Au composites, and their electrocatalytic properties

In this work, we developed a thiol-functionalized poly(3,4-ethylenedioxythiophene) hollow sphere (poly(EDOT-MeSH)/Au) polymer through a simple one-pot self-assembly method using polyvinylpyrrolidone (PVP) as a soft template. The monomer was used as both a reductant and a stabilizer to decorate gold nanoparticles (Au NPs). FTIR, XRD, EDX, SEM and TEM analyses were used to characterize the composite hollow spheres. The chemical bond between S and Au was confirmed by XPS. The electrochemical performance of the composite hollow spheres was determined by cyclic voltammetry (CV) and an ampere response timing current test. The results revealed that the poly(EDOT-MeSH)/Au hollow-sphere-based electrochemical sensor possesses excellent conductivity and high redox reversibility with detection limits (S/N = 3) of 0.2, 0.02, 0.08 and 0.05 μM in the linear ranges of 0.1–650 μM, 0.05–100 μM and 0.1–600 μM for the determination of ascorbic acid (AA), dopamine (DA), uric acid (UA) and nitrate ions (NO(2)(−)), respectively. The preparation method for these composites will further the development of this type of conducting polymer/gold nano-composite material modified electrochemical sensor for biological species.