Facile preparation of highly water-stable and flexible PEDOT:PSS organic/inorganic composite materials and their application in electrochemical sensors

The water-stability and adhesion are one of major problems of PEDOT:PSS film electrode nowadays due to easy swelling, disintegration, cracking-off, and falling of PEDOT:PSS film itself in water. The synergetic or complementary effects between organic and inorganic components can improve properties or performances of composite materials which have recently gained extensive interest in many fields. Two highly water-stable poly(3,4-ethylenedioxythiophene):poly(styrene-sulfonate) (PEDOT:PSS) composite materials based on an environmentally friendly polymer and the most studied and promising novel carbon nanomaterials available today are successfully prepared by the incorporation of the poly(vinyl alcohol) (PVA) and multiwalled carbon nanotubes (MWCNTs) or carboxylic group functionalized graphene (GR-COOH) into a commercially available aqueous dispersion of PEDOT:PSS. The two as-prepared highly water-stable PEDOT:PSS–PVA–novel carbon nanomaterials composite film electrodes with excellent adhesion properties are employed for the electrochemical determination of ternary mixture containing epinephrine, uric acid and tryptophan or niclosamide using linear sweep voltammetrys. PVA, a binding agent with adhesive properties, high tensile strength and good flexibility, can enhance the adhesion and binding force between PEDOT:PSS film and electrode interface, and improve swelling and degradation of PEDOT:PSS film in water. MWCNTs and GR-COOH with excellent electrical, optical, thermal and mechanical properties can enhance the electrocatalytic performance and sensing stability of PEDOT:PSS film electrodes. Especially, GR-COOH improves flexibility of PEDOT:PSS–PVA film. The fabricated film electrodes with superior water-stability and adhesion properties exhibit excellent electrocatalytic activity towards sensing application. Satisfactory results indicate that the prepared PEDOT:PSS organic/inorganic composites materials can provide a promising platform for the potential application of electrochemical modified electrode.