4 research outputs found
Redox-Driven Route for Widening Voltage Window in Asymmetric Supercapacitor
Although aqueous
asymmetric supercapacitors are promising technologies
because of their high-energy density and enhanced safety, their voltage
window is still limited by the narrow stability window of water. Redox
reactions at suitable electrodes near the water splitting potential
can increase the working potential. Here, we demonstrate a kinetic
approach for expanding the voltage window of aqueous asymmetric supercapacitors
using <i>in situ</i> activated Mn<sub>3</sub>O<sub>4</sub> and VO<sub>2</sub> electrodes. The underlying mechanism indicates
a specific potential of ∼1 V <i>vs</i> Ag/AgCl for
the oxidation of Mn<sup>4+</sup>-to-Mn<sup>7+</sup> at the positive
electrode and ∼ –0.8 V <i>vs</i> Ag/AgCl
for the reduction of V<sup>3+</sup>-to-V<sup>2+</sup> at the negative
electrode, which limits oxygen and hydrogen evolution reactions, respectively.
The as-fabricated aqueous asymmetric supercapacitor exhibited a working
voltage of 2.2 V with a high-energy density of 42.7 Wh/kg and a power
density of ∼1.1 kW/kg. This mechanism improves the voltage
window and energy and power densities
Redox-Driven Route for Widening Voltage Window in Asymmetric Supercapacitor
Although aqueous
asymmetric supercapacitors are promising technologies
because of their high-energy density and enhanced safety, their voltage
window is still limited by the narrow stability window of water. Redox
reactions at suitable electrodes near the water splitting potential
can increase the working potential. Here, we demonstrate a kinetic
approach for expanding the voltage window of aqueous asymmetric supercapacitors
using <i>in situ</i> activated Mn<sub>3</sub>O<sub>4</sub> and VO<sub>2</sub> electrodes. The underlying mechanism indicates
a specific potential of ∼1 V <i>vs</i> Ag/AgCl for
the oxidation of Mn<sup>4+</sup>-to-Mn<sup>7+</sup> at the positive
electrode and ∼ –0.8 V <i>vs</i> Ag/AgCl
for the reduction of V<sup>3+</sup>-to-V<sup>2+</sup> at the negative
electrode, which limits oxygen and hydrogen evolution reactions, respectively.
The as-fabricated aqueous asymmetric supercapacitor exhibited a working
voltage of 2.2 V with a high-energy density of 42.7 Wh/kg and a power
density of ∼1.1 kW/kg. This mechanism improves the voltage
window and energy and power densities
Redox-Driven Route for Widening Voltage Window in Asymmetric Supercapacitor
Although aqueous
asymmetric supercapacitors are promising technologies
because of their high-energy density and enhanced safety, their voltage
window is still limited by the narrow stability window of water. Redox
reactions at suitable electrodes near the water splitting potential
can increase the working potential. Here, we demonstrate a kinetic
approach for expanding the voltage window of aqueous asymmetric supercapacitors
using <i>in situ</i> activated Mn<sub>3</sub>O<sub>4</sub> and VO<sub>2</sub> electrodes. The underlying mechanism indicates
a specific potential of ∼1 V <i>vs</i> Ag/AgCl for
the oxidation of Mn<sup>4+</sup>-to-Mn<sup>7+</sup> at the positive
electrode and ∼ –0.8 V <i>vs</i> Ag/AgCl
for the reduction of V<sup>3+</sup>-to-V<sup>2+</sup> at the negative
electrode, which limits oxygen and hydrogen evolution reactions, respectively.
The as-fabricated aqueous asymmetric supercapacitor exhibited a working
voltage of 2.2 V with a high-energy density of 42.7 Wh/kg and a power
density of ∼1.1 kW/kg. This mechanism improves the voltage
window and energy and power densities
Redox-Driven Route for Widening Voltage Window in Asymmetric Supercapacitor
Although aqueous
asymmetric supercapacitors are promising technologies
because of their high-energy density and enhanced safety, their voltage
window is still limited by the narrow stability window of water. Redox
reactions at suitable electrodes near the water splitting potential
can increase the working potential. Here, we demonstrate a kinetic
approach for expanding the voltage window of aqueous asymmetric supercapacitors
using <i>in situ</i> activated Mn<sub>3</sub>O<sub>4</sub> and VO<sub>2</sub> electrodes. The underlying mechanism indicates
a specific potential of ∼1 V <i>vs</i> Ag/AgCl for
the oxidation of Mn<sup>4+</sup>-to-Mn<sup>7+</sup> at the positive
electrode and ∼ –0.8 V <i>vs</i> Ag/AgCl
for the reduction of V<sup>3+</sup>-to-V<sup>2+</sup> at the negative
electrode, which limits oxygen and hydrogen evolution reactions, respectively.
The as-fabricated aqueous asymmetric supercapacitor exhibited a working
voltage of 2.2 V with a high-energy density of 42.7 Wh/kg and a power
density of ∼1.1 kW/kg. This mechanism improves the voltage
window and energy and power densities