Electrochemical Preparation Of PPy Micro-Nano Structure With Water Soluble Polymer As Template

Water-soluble polymer as a template is an emerging, unique approach for the synthesisconductive polymer materials into well-defined micro/nanostructures. In recent years, thismethod is attracting more attention because simple, easy operation, and mild reactionconditions. In this article, conducting polymer Polypyrrole (PPy) micro/nanowires wereelectrochemical synthesized using water-soluble polymer, hydroxyethyl cellulose (HEC) andpolyacrylic acid gelatin (PAA), as a template. The molecular structure of the PPy nanowires,cauliflower-like PPy and ordered PPy microwires were characterized by FTIR, Raman spectra,X-ray diFigureraction (XRD) and Scanning electron microscopy (SEM), the element analysiswas conducted by energy dispersive X-ray (EDX). The electrochemical properties of the PPyproducts were evaluated by cyclic voltammetry in1M KCl solutions and the electricalconductivity was measured using the standard four-probe method. The fluorescence andwetting properties of the PPy products were also studied, respectively.The electrolyte was pyrrole, lithium perchlorate and aqueous solution, phosphatebuFigureer solution (pH=6.86) and buFigureer solution (pH=9.18), respectively. Theelectrochemical synthesis of PPy was carried out at room temperature. From the SEMmorphology observed, three kinds of polymers are cauliflower structure,explaining that thediFigureerent solvents a little eFigureect to the preparation of PPy morphology.PPy nanowires have been synthesized successfully in the presence of HEC, the wireswith diameter of ca.60~100nm and length of hundreds of nanometers. In order to verify thefunction of templates, using PAA as the template, in the same conditions prepared PPynanowires. However, the morphology of PPy are irregular which synthesized in the presenceof polyethylene glycol. The results show that the electrolyte containing water-solublepolymery is a necessar condition for the preparation of PPy nanowires. The influences ofrelated parameters on PPy morphology were systemically investigated. The experimentalresults indicate that PPy morphology could be influenced by applied potential, polymerizationtime and pH value. However, the electrochemical preparation methods and the solvent(aqueous solution and ethanol) have no eFigureects on PPy morphology. In this paper, we report a simple but effective dip-coating approach for preparing aspecial water soluble polymer template (that is, covering water soluble polymer on ITO glass),and then, highly ordered and straight PPy microwires are obtained by electrochemicaldeposition of pyrrole in ethanol solution, where the special HEC template is used as theworking electrode. The uniform PPy microwires with average diameter of ca.1~5μm andlength of hundreds of microns. The relationship between the orientation of PPy and thesoluble macromolecule was explored. Study on the influence of ITO surface treatment(surface hydrophilicity treatment, surface polishing, surface spraying and surfacemodification layer of PPy)，the results show that the order of the PPy microwires is good afterITO surface hydrophilicity treatment.The properties of cauliflower PPy, PPy nanowires and ordered PPy microwires werecharacterized by fluorescence, conductivity, electrochemical activity and surface hydrophobicability. The results show that PPy nanowires has the best excellent performance in threepolymers, suggesting that the PPy line size is the main factor aFigureecting its performance.