Hydrothermal encapsulation of VO₂(A) nanorods in amorphous carbon by carbonization of glucose for energy storage devices

Abstract

In recent decades, tremendous attention has been paid to the development of new electrode materials with high capacitance to meet the requirements of electrode materials in supercapacitors. Among vanadium oxides, VO(A) has recently received increasing attention due to its unique layered structure, phase transformation and applications in Li-ion batteries. However, few studies have focused on the electrochemical properties of VO(A) as electrochemical capacitors. Herein, we develop a facile hydrothermal method to prepare VO(A)@C core-shell structured composites by carbonization of glucose in the presence of VO nanowires. The electrochemical properties of the VO(A)@C core-shell composites are investigated as a supercapacitor electrode material for the first time; the composites show excellent pseudocapacitive behavior and display a specific capacitance as high as 179 F g at 1 A g. A flexible asymmetric supercapacitor device is fabricated using VO(A)@C composites and activated carbon and delivers an excellent capacitance of 0.5 F cm at a scan rate of 5 mV s. Replacing the aqueous electrolyte with a LiCl/PVA gel electrolyte can efficiently improve the cycling performance to 85% retention after 1600 cycles. The good electrochemical performance of the composites indicates their high potential as electrode materials for supercapacitors.

Review And Prospect of Mn3O4‐Based Composite Materials For Supercapacitor Electrodes

“…Compared with VO 2 (A)@C composites, the prepared materials show excellent cycle stability (85 % remain after 1600 cycles). [50] Based on this, these NWs are expected to be candidates for high capacitance, low cost and environmentally friendly ultracapacitor electrodes.…”

Engineering Na−Mo−O/Graphene Oxide Composites with Enhanced Electrochemical Performance for Lithium Ion Batteries

“…The past decade had witnessed significant progress in the synthesis of 1D nanostructured materials, such as electrospinning fiber technique, hydrothermal method and calcination, self‐sacrificial template method, most of which however require much cost and complicated procedure. Apart from the nanotechnologies, coupling with carbonaceous materials is another effect way to enhance the electrochemical performance by improving the electronic conductivity of the electrodes …”

Influence of the electrochemical properties of vanadium oxides on specific capacitance by molybdenum doping

“…Under these circumstances, vanadium oxides (VO x ) have drawn increasingly greater interest due to their advantages including low lost, stable chemical and physical properties, high specific capacity and energy density, etc. [6,[15][16][17][18][19][20][21][22][23][24][25][26][27][28][29]. The multiple valence states (V 5+ , V 4+ , V 3+ and V 2+ ) of vanadium can make it possible to form different kinds of oxides.…”