One-step hydrothermal synthesis of graphene decorated V₂O₅ nanobelts for enhanced electrochemical energy storage

摘要

Graphene-decorated V₂O₅ nanobelts (GVNBs) were synthesized via a low-temperature hydrothermal method in a single step. V₂O₅ nanobelts (VNBs) were formed in the presence of graphene oxide, a mild oxidant, which also enhanced the conductivity of GVNBs. From the electron energy loss spectroscopy analysis, the reduced graphene oxide (rGO) are inserted into the layered crystal structure of V₂O₅ nanobelts, which further confirmed the enhanced conductivity of the nanobelts. The electrochemical energy-storage capacity of GVNBs was investigated for supercapacitor applications. The specific capacitance of GVNBs was evaluated using cyclic voltammetry (CV) and charge/discharge (CD) studies. The GVNBs having V₂O₅-rich composite, namely, V₃G₁ (VO/GO = 3:1), showed superior specific capacitance in comparison to the other composites (V₁G₁ and V₁G₃) and the pure materials. Moreover, the V₃G₁ composite showed excellent cyclic stability and the capacitance retention of about 82% was observed even after 5000 cycles.