Agar-based aqueous electrolytes for electrochemical capacitors with reduced self-discharge

Menzel, Jakub; Frąckowiak, Elżbieta; Fic, Krzysztof

doi:10.1016/j.electacta.2019.135435

Cited by 59 publications

(55 citation statements)

References 68 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In previous work, the potential windows of the same kind of SCs typically reached up to 1.0 V because of the unstable cycling behavior of a SC in an acidic electrolyte. In our work, we developed a simple route utilizing an ecologically compatible polymer, named agarose [ 18 , 19 , 20 ], as a novel binder (instead of polyvinylidene fluoride, PVDF, or polytetrafluoroethylene, PTFE) to fabricate an active carbon–carbon symmetric aqueous SC. A wider potential window with an operating voltage of 1.8 V, attributed to a large overpotential for the hydrogen-evolution reaction (HER), was achieved with a carbon-fiber cloth (CFC) packaging the SC and with sulfuric acid as the current collector and aqueous electrolyte, achieving a great cycling stability with a 94.2% capacitance retention after 10,000 cycles at 2 A/g.…”

Section: Introductionmentioning

confidence: 99%

1.8 V Aqueous Symmetric Carbon-Based Supercapacitors with Agarose-Bound Activated Carbons in an Acidic Electrolyte

Lai

Hsu

et al. 2021

Nanomaterials

View full text Add to dashboard Cite

The specific energy of an aqueous carbon supercapacitor is generally small, resulting mainly from a narrow potential window of aqueous electrolytes. Here, we introduced agarose, an ecologically compatible polymer, as a novel binder to fabricate an activated carbon supercapacitor, enabling a wider potential window attributed to a high overpotential of the hydrogen-evolution reaction (HER) of agarose-bound activated carbons in sulfuric acid. Assembled symmetric aqueous cells can be galvanostatically cycled up to 1.8 V, attaining an enhanced energy density of 13.5 W h/kg (9.5 µW h/cm2) at 450 W/kg (315 µW/cm2). Furthermore, a great cycling behavior was obtained, with a 94.2% retention of capacitance after 10,000 cycles at 2 A/g. This work might guide the design of an alternative material for high-energy aqueous supercapacitors.

show abstract

Section: Introductionmentioning

confidence: 99%

1.8 V Aqueous Symmetric Carbon-Based Supercapacitors with Agarose-Bound Activated Carbons in an Acidic Electrolyte

Lai

Hsu

et al. 2021

Nanomaterials

View full text Add to dashboard Cite

show abstract

“…No capacitance remained in the capacitors after only 42.13 h. The discharge curves after the self-discharge test period of these four systems (tested after Figure 4a,b) are exhibited in Figure 4c, in which Zn-BP-WiS, Zn-BP-WiS-2.5 V, and Zn-BP-PC showed similar discharge curves, while the retained capacitance of BP-BP-WiS was much low. The capacitance retention after self-discharge test of different supercapacitors [51][52][53][54] and ion hybrid capacitor systems [15] are compared in Figure 4d. The initial discharge voltage of most of the other capacitors was lower than 1.6 V and their self-discharge time was lower than 80 h. By contrast, the Zn-BP-WiS and Zn-BP-PC presented in this work delivered absolute superiority in both anti-self-discharge time and initial discharge voltage.…”

Section: Resultsmentioning

confidence: 99%

Phosphorene as Cathode Material for High‐Voltage, Anti‐Self‐Discharge Zinc Ion Hybrid Capacitors

Huang

Chen

et al. 2020

Advanced Energy Materials

179

124

View full text Add to dashboard Cite

It is generally believed that supercapacitors are mainly characterized by high power density and low energy density; therefore, significant efforts have been focused on improving the energy density of electrode materials. [2,3] The potential windows of aqueous supercapacitors, especially for those based on acidic and alkaline electrolytes, are limited by their electrolyte decomposition voltage (1.23 V). Several researchers showed potentials reaching only ≈1 V, which heavily impeded the practical application of supercapacitors. [4][5][6] Two methods that have proven effective in resolving the narrow voltage range that results from water decomposition entail replacing the water electrolyte with "water in salt" (WiS) electrolytes and organic electrolytes, respectively. [7,8] The WiS electrolytes were proposed by Wang and co-workers in 2015, and their use expanded the potential window to ≈3.0 V due to the formation of an electrode-electrolyte interphase. [9] The close interaction between water molecules and the electrolyte in ultrahigh concentration makes it difficult for water to decompose, thus effectively broadening the electrochemical operating voltage range. As for the organic electrolytes, the influence of water electrolysis is exclusive, and the electrolyte operating voltage range only depends on its electrochemical stability voltage. [10][11][12] Following these two approaches, the potential windows can be effectively expanded, which is the basic requirement for supercapacitors to deliver a high output voltage.Another neglected property of supercapacitors is their self-discharge rate, the low capacity retention in open circuit state makes the supercapacitors less effective in practical applications. A general method was required to enhance the anti-self-discharge properties. The intrinsic reason for the fastself-discharge speed is that when both anode and cathode materials store electricity through adsorption behaviors, they have a barely satisfactory ion limiting ability and the ions adsorbed on the electrode during the charging process will soon diffuse into the electrolyte due to the concentration gradient. Hybrid ion capacitors can be constructed to inhibit self-discharge by incorporating insertion-type and conversion-type batterytype electrodes that have stronger force for limiting ions than through simple adsorption behaviors. For this, one of the Output voltage and self-discharge rate are two important performance indices for supercapacitors, which have long been overlooked, though these play a very significant role in their practical application. Here, a zinc anode is used to construct a zinc ion hybrid capacitor. Expanded operating voltage of the hybrid capacitor is obtained with novel electrolytes. In addition, significantly improved anti-self-discharge ability is achieved. The phosphorene-based zinc ion capacitor exploiting a "water in salt" electrolyte with a working potential can reach 2.2 V, delivering 214.3 F g −1 after 5000 cycles. The operating voltage is further extended to 2.5 V through the...

show abstract

“…They obtained capacitances in the mF.g −1 range and good cyclability, with the device retaining 100% of its initial capacity after 1000 cycles [ 124 ]. Menzel et al [ 125 ] also described a capacitor based on an agar gel and carbon electrodes. As for Avila- Niño et al, recyclability was not detailed, even if all constituents of the device were intrinsically degradable.…”

Section: Discussionmentioning

confidence: 99%

Sensors Made of Natural Renewable Materials: Efficiency, Recyclability or Biodegradability—The Green Electronics

Piro

Tran

Thu

2020

Sensors

View full text Add to dashboard Cite

Nowadays, sensor devices are developing fast. It is therefore critical, at a time when the availability and recyclability of materials are, along with acceptability from the consumers, among the most important criteria used by industrials before pushing a device to market, to review the most recent advances related to functional electronic materials, substrates or packaging materials with natural origins and/or presenting good recyclability. This review proposes, in the first section, passive materials used as substrates, supporting matrixes or packaging, whether organic or inorganic, then active materials such as conductors or semiconductors. The last section is dedicated to the review of pertinent sensors and devices integrated in sensors, along with their fabrication methods.

show abstract

Agar-based aqueous electrolytes for electrochemical capacitors with reduced self-discharge

Cited by 59 publications

References 68 publications

1.8 V Aqueous Symmetric Carbon-Based Supercapacitors with Agarose-Bound Activated Carbons in an Acidic Electrolyte

1.8 V Aqueous Symmetric Carbon-Based Supercapacitors with Agarose-Bound Activated Carbons in an Acidic Electrolyte

Phosphorene as Cathode Material for High‐Voltage, Anti‐Self‐Discharge Zinc Ion Hybrid Capacitors

Sensors Made of Natural Renewable Materials: Efficiency, Recyclability or Biodegradability—The Green Electronics

Contact Info

Product

Resources

About