In-situ synthesis of core/shell structured polypyrrole/hydroquinone nano-beads and electrochemical capacitance investigations

A new route to prepare core/shell structured polypyrrole (PPy)/hydroquinone nano-beads have been proposed via an in-situ chemical oxidative polymerization. The core template, p-benzoquinone, is demonstrated to work as an oxidizing agent for the in-situ polymerization of PPy, and to be reduced to 1,4-hydroquinone after the reaction. The structure and morphology of the nano-beads have been characterized by held-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FT-IR) spectra. The cyclic voltammetry (CV), impedance and galvanostatic charge/discharge analysis demonstrate that PPy contributes electronic conductive channels for hydroquinone and hydroquinone works as a pseudocapacitance component. The prepared PPy/hydroquinone nano-beads exhibit brilliant electrochemical properties of a specific capacitance of 91.6 F g(-1) at a scan rate of 5 mV s(-1) and enhanced stability of about 63.1 F g(-1) after 500-cycle scanning at a current density of 0.5 A g(-1). (C) 2014 Elsevier B.V. All rights reserved,