Abstract
Rechargeable aqueous zinc ion hybrid capacitors (ZIHCs), as an up-and-comer aqueous electrochemical energy storage system, endure in their infancy because of the substandard reversibility of Zn anodes, structural deterioration of cathode materials, and narrow electrochemical stability window. Herein, a scalable approach is described that addresses Zn-anode/electrolyte interface and cathode materials associated deficiencies and boosts the electrochemical properties of ZIHCs. The Zn-anode/electrolyte interface is self-regulated by alteration of the traditional Zn2+ electrolyte with Na-based supporting salt without surrendering the cost, safety, and green features of the Zn-based system which further validates the excellent reversibility over 1100 h with suppressed hydrogen evolution. The deficits of cathode materials were overcome by using a high-mass loaded, oxygen-rich, 3D, multiscaled graphene-like carbon (3D MGC) cathode. Due to the multiscaled texture, high electronic conductivity, and oxygen-rich functional groups of 3D MGC, reversible redox capacitance was obtained with a traditional adsorption/desorption mechanism. Prototype ZIHCs containing the modified electrolyte and an oxygen-rich 3D MGC cathode resulted in battery-like specific energy (203 Wh kg−1 at 1.6 A g−1) and supercapacitor-type power capability (4.9 kW kg−1 at 8 A g−1) with outstanding cycling durability (96.75% retention over 30 000 cycles at 10 A g−1). These findings pave the way toward the utilization of highly efficient ZIHCs for practical applications. (Figure presented.).
Original language | English |
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Article number | e12344 |
Journal | InfoMat |
Volume | 4 |
Issue number | 10 |
DOIs | |
State | Published - Oct 2022 |
Keywords
- electrolyte additive
- graphene-like carbon
- interface
- multivalent ion capacitor
- zinc