Surfactant Effects on the Morphology and Pseudocapacitive Behavior of V₂O₅⋅H₂O

Abstract

To overcome the drawback of low electrical conductivity within supercapacitor applications, several surfactants are used for nanoscale V2 O5 to enhance the specific surface area. Polyethylene glycol 6000 (PEG-6000), sodium dodecylbenzene sulfonate (SDBS), and Pluronic P-123 (P123) controllers, if used as soft templates, easily form large specific surface area crystals. However, the specific mechanism through which this occurs and the influence of these surfactants is not clear for V2 O5 ⋅H2 O. In the present study, we aimed to investigate the mechanism of crystal growth through hydrothermal processes and the pseudocapacitive behavior of these crystals formed by using diverse surfactants, including PEG-6000, SDBS, and P123. Our results show that different surfactants can dramatically influence the morphology and capacitive behavior of V2 O5 ⋅H2 O powders. Linear nanowires, flower-like flakes, and curly bundled nanowires can be obtained because of electrostatic interactions in the presence of PEG-6000, SDBS, and P123, respectively. Furthermore, the electrochemical performance of these powders shows that the nanowires, which are electrodes mediated by PEG-6000, exhibit the highest capacitance of 349 F g(-1) at a scan rate of 5 mV s(-1) of all the surfactants studied. However, a symmetric P123 electrode comprising curly bundled nanowires with numerous nanopores showed an excellent and stable specific capacitance of 127 F g(-1) after 200 cycles. This work is beneficial to understanding the fundamental role of the surfactant in the assisted growth of V2 O5 ⋅H2 O and the resulting electrochemical properties of the pseudocapacitors, which could be useful for the future design of appropriate materials.

High‐Performance Flexible Supercapacitors Based on Ionogel Electrolyte with an Enhanced Ionic Conductivity

“…There were no evident peaks at the end of the sweep, indicating a negligible overpotential or that no side reaction occurred in the cell. As displayed in Figure (b), the GCD curve shows a typical triangular form with nearly a straight line for the different current densities, indicating excellent electrochemical performance . The IR drop increases moderately with increasing current density, which is attributed to the high viscosity of the ILs, which prevents fast ion transport at the electrode‐electrolyte interface at high current densities (Figure (c)).…”

V2O5 encapsulated MWCNTs in 2D surface architecture: Complete solid-state bendable highly stabilized energy efficient supercapacitor device

“…Sol-gel derived nanoporous V 2 O 5 attains capacitance of 214 F g −1 in 2 M KCl6 whereas the same electrolyte at the same concentration through co-precipitation method yields 349 F g −1 specific capacitance78. Instead of using just the metal oxide, nanocomposites with MWCNTs will further boost the electrochemical properties of the resulting electrodes.…”

Vanadium Pentoxide with H2O, K+, and Na+ Spacer between Layered Nanostructures for High‐Performance Symmetric Electrochemical Capacitors

“…Finally, the precipitate was heat-treated in the muffle furnace at 400 °C for 3 h. The VOSO 4 · xH 2 O synthesis process is schematically depicted in Scheme 1 and the chemical reactions involve in this synthesis process are represented in Equations (8)(9)(10) Fabrication of Electrodes and Symmetric Supercapacitor: The supercapacitor electrodes were fabricated using Ti substrate of area 1 × 1 cm 2 as a current collector. In the synthesis process, the starting materials of VOSO 4 ·xH 2 O and (NH 4 ) 2 S 2 O 8 , K 2 S 2 O 8 , or Na 2 S 2 O 8 were mixed in 50 mL of deionized (DI) water in the ratio of 1:1 and stirred for 30 min at room temperature.…”

“…[7] Among the various metal oxides, vanadium pentoxide (V 2 O 5 ) is reflected to be the most capable candidate for pseudocapacitor owing to its natural abundance and existence of variable oxidation states from +2 to +5 (VO, V 2 O 3 , VO 2 , and V 2 O 5 ). [9,10] So, vanadium pentoxide nanostructures have been the most regarded materials in various applications, [11] such as batteries, [12][13][14] supercapacitors, [15,16] catalyst, [17] optical switching, [18] and energy-saving devices. [9,10] So, vanadium pentoxide nanostructures have been the most regarded materials in various applications, [11] such as batteries, [12][13][14] supercapacitors, [15,16] catalyst, [17] optical switching, [18] and energy-saving devices.…”