Recent advances and future perspectives for aqueous zinc-ion capacitors

Abstract

The ion hybrid capacitor is expected to combine the high specific energy of battery-type materials and the superior specific power of capacitor-type materials, being considered as a promising energy storage technique. Particularly, the aqueous zinc-ion capacitors (ZIC) possessing merits of high safety, cost-efficiency and eco-friendliness, have been widely explored with various electrode materials and electrolytes to obtain excellent electrochemical performance. In this review, we first summarized the research progress on enhancing the specific capacitance of capacitor-type materials and reviewed the research on improving the cycling capability of battery-type materials under high current densities. Then, we looked back on the effects of electrolyte engineering on the electrochemical performance of ZIC. Finally, the research challenges and development directions of ZIC have been proposed. This review provides a guidance for the design and construction of the high-performance ZIC.

Arrayed Heterostructures of MoS2 Nanosheets Anchored TiN Nanowires as Efficient Pseudocapacitive Anodes for Fiber-Shaped Ammonium-Ion Asymmetric Supercapacitors

“…With the further development of artificial intelligence and the Internet of things, portable smart wearable electronic devices will undergo rapid development. − Thus, as a crucial part, the exploitation of flexible wearable energy storage devices and technologies with good safety, cost-effectiveness, environmental friendliness, and long lifetimes will make extraordinary sense. , As an innovative and highly promising energy storage device, fiber-shape supercapacitors have attracted substantial attention ascribed to their light weight, small volume, outstanding flexibility, and weaving. − However, the high cost, limited sources, and side reaction issues have severely affected the extensive applications of metallic cations (for instance, Li + , Na + , K + , Mg 2+ , Zn 2+ , Ca 2+ , and Al 3+ ) in energy storage devices. − Conversely, nonmetallic cationic charge carriers like H + , H 3 O + , and NH 4 + have only acquired small appeal despite their distinct advantages of light molar mass, high ionic conductivity, abundant resources, grid-scale storage, less corrosiveness, and the hydrogen evolution reaction (HER). − …”

“…1−3 Thus, as a crucial part, the exploitation of flexible wearable energy storage devices and technologies with good safety, cost-effectiveness, environmental friendliness, and long lifetimes will make extraordinary sense. 4,5 As an innovative and highly promising energy storage device, fiber-shape supercapacitors have attracted substantial attention ascribed to their light weight, small volume, outstanding flexibility, and weaving. 6−11 However, the high cost, limited sources, and side reaction issues have severely affected the extensive applications of metallic cations (for instance, Li + , Na + , K + , Mg 2+ , Zn 2+ , Ca 2+ , and Al 3+ ) in energy storage devices.…”

Revealing the Self-Doping Defects in Carbon Materials for the Compact Capacitive Energy Storage of Zn-Ion Capacitors

“…Hybrid ion capacitors are promising energy storage devices thanks to the integrated merits of both high energy and power densities originating from the battery-type anode and the capacitor-type cathode. − Zn-ion capacitors typically assembled by a Zn anode, zinc salt electrolytes, and a porous carbon cathode have received great attention in recent years owing to the high theoretical capacity (823 mAh g –1 /5855 mAh cm –3 ), low redox potential (−0.76 V vs standard hydrogen reference), robust electrochemical kinetics, and resource abundance of Zn. − Large-surface-area porous carbons (1000–4000 m 2 g –1 ) with the electrical double-layer behavior are commonly used as the cathode materials , but show unsatisfactory capacitance to match the Zn anode due to their low specific areal capacitance contribution ( C s < 0.2 F m –2 as summarized from the literature in Table S1). − What is more, a highly developed porous structure usually causes a low density of porous carbons (<0.6 g cm –3 ), resulting in an unsatisfactory volumetric performance that cannot meet the ever-increasing requirements for lightweight and miniaturized devices. , Therefore, improving the capacitance of dense carbon materials by novel active site design is urgently needed yet still challenging for future development of Zn-ion capacitors.…”

Introducing micropores into carbon nanoparticles synthesized via a solution plasma process by thermal treatment and their charge storage properties in supercapacitors

“…2,3 They can be classied into three main types based on their charge storage mechanism: (i) electric double layer capacitors (EDLCs), which store charges through electrostatic interaction on the surface of the electrode (non-faradaic process), [4][5][6] (ii) pseudocapacitors (PCs), which store charges through reversible redox reactions at the electrode-electrolyte interface (faradaic process), 7,8 and (iii) hybrid supercapacitors, which combine both EDLC and PC behaviors to achieve high energy and power density. [9][10][11][12] The electrode materials have been proven to play a vital role in determining the charge storage performance and stability of supercapacitors. [1][2][3] Various families of materials have been investigated and used as electrode materials in both research and commercial products, including porous carbons, [13][14][15][16] metal oxide, 17 metal sulde, 18 metal nitride, 19 MXenes, 20 metalorganic frameworks, 21 and mixtures thereof.…”