Facile synthesis of TiO2/rGO neatly electrodeposited on carbon fiber applied as ternary electrode for supercapacitor

Abstract

A direct and quick approach to performer rGO (reduced graphene oxide) and TiO2 (titanium oxide) depositions using electrochemical techniques to reduce GO on CF substrate (rGO/CF) with subsequent TiO2 nanoparticles electrodeposition to produce ternary nanocomposites TiO2/rGO/CF is presented. A new bath solution consisting of titanium chloride, H2O2 and supporting salt LiClO4 was develop in order to simplify and reduce the preparation time of TiO2 synthesis. Scanning electron microscopy images showed irregular and flakes-like shape aggregates with high particle density on CF substrate characteristic of rGO morphology. Homogeneous distribution of TiO2 nanoparticles on TiO2/rGO/CF surfaces were observed on graphene sheets without modifying their morphologies. The CV curves presented a quasi-rectangular shape, indicating that the charge storage occurs preferentially through of the TiO2/rGO/CF electric double layer. Galvanostatic tests showed the highest time of the charge/discharge for TiO2/rGO/CF-5 sample, probably attributed to its surface area increase, improving its charge storage capacity. These results assured that TiO2/rGO/CF ternary composite has great potential as new electrode for supercapacitor application.