ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Synthesis of vanadium oxides nanosheets as anode material for asymmetric supercapacitor

Zhi-Qiang Hou, Zhi-Guang Yang, and Yong-Ping Gao

Zhou Kou Normal University, Henan, China

E-mail: houzq@hust.edu.cn

Abstract: Vanadium oxides (V₂O₅) have been intensely investigated for advanced supercapacitors due to its extensive multifunctional properties of typical layered structure and multiple stable oxide states of vanadium in its oxides. In this study, V₂O₅ nanosheets are synthesized via V₂O₅ xerogel solvothermal reaction in ethanol solvent at 200 °C for 12 h. The V₂O₅ nanosheets facilitate the easy accessibility of ions and can provide more area available for electrochemical reactions. We have achieved the highest specific capacitance of 298 F/g and good rate discharge for V₂O₅ electrodes. Notably, the capacitance still retains a high retention rate of 85% after 10,000 cycles at 200 mV/s. Furthermore, asymmetric supercapacitors is assembled based on V₂O₅ nanosheets and active carbon electrode, and a specific capacitance of 13.2 F/g is obtained at 1 A/g, with a energy density of 4.7 Wh/kg at a power density of 0.798 kW/kg and remains 2.28 Wh/kg at 7.992 kW/kg. Based on these results, the asymmetric supercapacitor exhibits a good cycle life with 77.3% capacitance retention after 3000 cycles. It suggests that the V₂O₅ nanosheets are promising electrode material for electrochemical supercapacitors.

Keywords: V₂O₅ xerogel ; V₂O₅ nanosheets ; Specific capacitance ; Supercapacitor 

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-018-0504-9

Chemical Papers 72 (11) 2849–2857 (2018)