Polyethylene glycol assisted synthesis of V2O5 nanofibers as an efficient electrode material for symmetric supercapacitors

The performance of supercapacitors is strongly related to the high surface area, morphology (shape and size), the porosity of materials, fast ion passage channels, structural stability, and variable oxidation state of electrode material. In the present work, we have investigated the role of polyethylene glycol (PEG) on the crystal structure, morphology, and electrochemical behavior of V2O5 nanoparticles. We demonstrated the advantages of applying PEG as an effective modifier for the synthesis of V2O5 nanofibers. The dual role of PEG such as a structure directing agent and as a precursor for forming a carbon matrix assists in inhibiting crystallite growth and elevates the electronic conductivity of the V2O5 nanofibers. The V2O5-PEG/Flexible stainless-steel mesh (FSSM) exhibited a specific capacitance of 520.3 F g(-1) at a current density of 2 mA cm(-2) and excellent cyclic stability (87% over 2000 cycles) which is higher than the bare V2O5. Furthermore, the assembled V2O5-PEG/FSSM-based symmetric capacitor device delivers a specific capacitance of 81.7 F g(-1) with an energy density of 16.3Wh kg(-1). The good capacitive performance of V2O5-PEG/FSSM is due to the intercalated PEG molecules into the V2O5 nanofibers which provide a high specific surface area, and interconnected nanofiber network-like morphology with wide pores.

Automated summary

The role of polyethylene glycol (PEG) on the crystal structure, morphology, and electrochemical behavior of V2O5 nanoparticles was investigated in this study. PEG was found to be an effective modifier for the synthesis of V2O5 nanofibers, acting as a structure directing agent and a precursor for forming a carbon matrix. The V2O5-PEG/FSSM exhibited a specific capacitance of 520.3 F g(-1) and excellent cyclic stability, outperforming the bare V2O5. The assembled V2O5-PEG/FSSM-based symmetric capacitor device delivered a specific capacitance of 81.7 F g(-1) with an energy density of 16.3Wh kg(-1), attributed to the intercalated PEG molecules providing a high specific surface area and interconnected nanofiber network-like morphology.