Novel Hybrid Nanoparticles of Vanadium Nitride/Porous Carbon as an Anode Material for Symmetrical Supercapacitor

摘要

Hybrid materials of vanadium nitride and porous carbon nanoparticles (VN/PCNPs) were fabricated by a facile pyrolysis process of vanadium pentoxide (V_(2)O_(5)) xerogel and melamine at relatively low temperature of 800 °C for supercapacitor application. The effects of the feed ratio of V_(2)O_(5) to melamine ( r ), and nitrogen flow rate on the microstructure and electrochemical performance were also investigated. It was found that the size of the as-synthesized nanoparticles is about 20?nm. Both r value and N_(2) flow rate have enormous impacts on morphology and microstructure of the nanoparticle, which correspondingly determined the electrochemical performance of the material. The VN/C hybrid nanoparticles exhibited high capacitive properties, and a maximum specific capacitance of 255.0?F?g~(?1) was achieved at a current density of 1.0?A?g~(?1) in 2?M KOH aqueous electrolyte and the potential range from 0 to ?1.15?V. In addition, symmetrical supercapacitor fabricated with the as-synthesized VN/PCNPs presents a high specific capacitance of 43.5?F?g~(?1) at 0.5?A?g~(?1) based on the entire cell, and an energy density of 8.0 Wh?kg~(?1) when the power density was 575?W?kg~(?1). Even when the power density increased to 2831.5?W?kg~(?1), the energy density still remained 6.1 Wh?kg~(?1).Graphical Open image in new window.