Asymmetric supercapacitor based on VS₂ nanosheets and activated carbon materials

Abstract

VS 2 nanosheets as the positive electrode and the activated carbon (AC) as the negative electrode with a 6 M KOH solution as electrolyte were fabricated as an asymmetric supercapacitor. These materials were combined to maximize the specific capacitance and to enlarge the potential window, therefore improving the energy density of the device. A specific capacitance of 155 F g -1 at 1 A g -1 with a maximum energy density as high as 42 Wh kg -1 and a power density of 700 W kg -1 was obtained for the asymmetric supercapacitor within the voltage range of 0 -1.4 V. The supercapacitor also exhibited a good stability with ∼ 99% capacitance retention and no capacitance loss after 5000 cycles at a current density of 2 Ag -1 .

Facile hydrothermal synthesis of hexapod-like two dimensional dichalcogenide NiSe2 for supercapacitor

“…Till date, such efforts have been achieved through novel two dimensional (2D) layered materials including graphene, reduced graphene oxides and chalcogenides [2][3][4][5]. In particular, 2D transition metal dichalcogenides (TMD) such as NiS 2 , CoS 2 , MoS 2 , VS 2 , WS 2 and MoSe 2 have been proved as high performance supercapacitor electrode materials [6][7][8][9][10][11]. However, to the best of our knowledge, reports on 2D TMD hexapod-like NiSe 2 as the supercapacitor electrode material has not been reported earlier.…”

Cytotoxicity of Exfoliated Layered Vanadium Dichalcogenides

“…In search of more exciting discoveries and better performances, other transition metals were also explored; notably the neighbouring Group 5 vanadium dichalcogenides. They have shown competitive performances for similar applications as their Group 6 counterparts (i.e., electrochemical hydrogen production, batteries and capacitors).…”

Reconciled Nanoarchitecture with Overlapped 2 D Anatomy for High‐Energy Hybrid Supercapacitors

“…A capacitance value of 211 F g −1 is achieved at a current density of 1 A g −1 . This superior capacitance is significantly higher than that previously reported in the literature . The capacitance maintains 96 % of its value at 1 A g −1 if the current density is doubled (2 A g −1 ).…”

“…The signal at a BE of 162.15 eV indicates the existence of low‐coordination sulfur ions at the surface, and the signal at a BE of 163.25 eV indicates metal bonding to sulfur . The V 2p spectrum in Figure D shows two signals at BEs of 513.38V and 520.65 eV, and they can be attributed to the +4 valance state of vanadium . The XPS chemical composition measurements reveal a 1:1.99 atomic ratio of V/S, which is almost identical to the stoichiometric ratio of VS 2 .…”

“…The synthesized VS 2 showed high conductivity and a considerable specific capacitance of 4760 μF cm −2 . Masikhwa et al . reported the use of a hydrothermal reaction to synthesize VS 2 nanosheets, which were used for the first time in the fabrication of an asymmetric supercapacitor showing a specific capacitance of 155 F g −1 and an energy density of 42 Wh Kg −1 at a power density of 0.70 kW kg −1 .…”