Synthesis of polypyrrole–titanium dioxide brush-like nanocomposites with enhanced supercapacitive performance

Abstract

In this work, a kind of polypyrrole (PPy) layer–PPy nanowire–TiO₂ nanotube brush-like composite has been successfully prepared. Highly ordered and free-standing TiO₂ nanotube arrays were prefabricated via an anodizing method, pyrrole was then filled and polymerized in the nanotube arrays through an electrochemical deposition route to form a nanowire-in-tube structure together with a PPy layer outside. The morphology of the as-prepared hybrid nanostructure was observed by scanning electron microscope (SEM), the PPy filling in the TiO₂ nanotube was confirmed by Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy. When investigated as an anode material for supercapacitors, the as-obtained PPy/TiO₂ could deliver a capacity of 446 F g⁻¹ at a current density of 15 A g⁻¹ even after 1000 cycles, which is much higher than individual TiO₂ nanotubes and PPy, respectively. The smart nanostructure of the PPy/TiO₂ nanocomposites makes a prominent contribution to the excellent electrochemical performance.