• YUTING HUANG

Articles written in Bulletin of Materials Science

• Facile synthesis and characterization of rough surface V$_2$O$_5$ nanomaterials for pseudo-supercapacitor electrode material with high capacitance

V$_2$O$_5$ nanomaterials with rough surface were synthesized using commercial V$_2$O$_5$, ethanol (EtOH) and H$_2$O as the starting materials by a simple hydrothermal route and combination of calcination. The electrochemical properties ofV$_2$O$_5$ nanomaterials as electrodes in a supercapacitor device were measured using cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD) method. V$_2$O$_5$ nanomaterials exhibit the specific capacitance of 423 F g$^{−1}$ at the current density of 0.5 A g$^{−1}$ and retain 327 F g$^{−1}$ even at the high current density of 10 A g$^{−1}$. The influence of the ratio of EtOH/H$_2$O, the calcined time and temperature on the morphology, purity and electrochemical property of the products is discussed in detail. The results revealed that the ratio of EtOH/H$_2$O $=$ 10/25 and calcination at 400$^{\circ}$C for 2–4 h are favourable for preparing V$_2$O$_5$ nanomaterials and they exhibited the best electrochemical property. The novel morphology and high specific surface area are the main factors that contribute to high electrochemical performance of V$_2$O$_5$ nanomaterials during the charge–discharge processes. It turns out that V$_2$O$_5$ nanomaterials with rough surface is an ideal material for supercapacitor electrode in the present work.

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

Molybdenum (Mo)-doped vanadium dioxide (VO$_2$(B)) nanobelts were successfully synthesized using commercial vanadium pentoxide (V$_2$O$_5$) as the starting material and ammonium molybdate as the dopant by a simple hydrothermal route. Then, Mo-doped VO2(B) nanobelts were transformed to Mo-doped V$_2$O$_5$ nanobelts by calcination at 400$^{\circ}$C under an air atmosphere. The samples were characterized by X-ray powder diffraction,energy-dispersive X-ray spectrometer, elemental mapping, X-ray photoelectron spectroscopy, X-ray fluorescence and transmission electron microscopy techniques. The results showed that Mo-doped VO$_2$(B) and V$_2$O$_5$ solid solution with high purity were obtained. The electrochemical properties of Mo-doped VO$_2$(B) and V$_2$O$_5$ nanobelts as supercapacitor electrodes were measured using cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD). The specific capacitance of VO$_2$(B) nanobelts slightly declines with Mo doping, however, the specific capacitance of V$_2$O$_5$ nanobelts greatly improves with Mo doping. Mo-doped V$_2$O$_5$ nanobelts exhibit the specific capacitance as high as 526 F g$^{−1}$ at the current density of 1 A g$^{−1}$. Both CV and GCD curves show that they have good rate capability and retain 464, 380, 324 and 273 F g$^{−1}$ even at a high-current density of 2, 5, 10 and 20 A g$^{−1}$, respectively. It turns out that Mo-dopedV$_2$O$_5$ nanobelts are ideal materials for supercapacitor electrodes in the present work.

• Bulletin of Materials Science

Volume 45, 2022
All articles
Continuous Article Publishing mode

• Dr Shanti Swarup Bhatnagar for Science and Technology

Posted on October 12, 2020

Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
Chemical Sciences 2020