High‐Performance Aqueous Zinc Batteries Based on Organic/Organic Cathodes Integrating Multiredox Centers

Abstract

V vs the standard hydrogen electrode), ultrahigh theory capacity (820 mAh g −1 ), low cost, fast kinetics, and superior reliability, aqueous zinc-ion batteries (ZIBs) have attracted extensive attention among various rechargeable batteries. [5][6][7][8] However, the energy density and output power density of state-of-the-art ZIBs are mainly limited by the unsatisfactory cathode materials, especially under the commercial mass loading (> 10 mg cm −2 ). [9,10] Considerable research efforts have been put into the design of high performance cathode hosts, including Mn-based, V-based transition metal oxides/sulfides, Prussian blue analogues, and organic compounds. [11][12][13] Compared to intercalation-type inorganic counterparts with unstable structures and sluggish ionic diffusion, organic cathodes are promising candidates for advanced aqueous ZIBs due to their lightweight, sustainable, flexible, and tunable structures. [12,14,15] During energy storage/release process of Zn-organic batteries, the cations (Zn 2+ or H + ) are only act to coordinate the charge of active functional group based redox reactions. [16][17][18] Hence, the merely chemical bond rearrangement in organic hosts can contribute to the improved rate capability and cycling stability of ZIBs. [19][20][21] In the past few years, a lot of organic and organic-inorganic hosts have been successfully reported as cathodes for high performance ZIBs. However, the reported polyaniline (PANI) intercalated MnO 2 , [22] PANI intercalated V 2 O 5 , [23] and polypyrrole (PPy) encapsulated Mn 2 O 3 cathodes with the enhanced rate performances were based on the mass loading less than 3 mg cm −2 , which is not conducive to the practical application of aqueous zinc ion batteries. [24] To date, the reversible electrochemical reactions between cations and redox groups of CO, CN, and CN have been studied in Zn-organic batteries. [25][26][27][28] For instance, Chen's group first reported cially calix (C4Q) cathode for building high capacity and long lifespan Zn-organic batteries, yet their large scale applications are limited by the complex synthesis process. [29] Stoddart's group studied phenanthrenequinone-based macrocycle (PQ-Δ) organic cathode, which demonstrates the insertion of hydrated zinc ions and robust triangular structure are benefit to achieve Zn-organic batteries with superior stability. [30] Yet, their low redox potential and unsatisfactory capacity have no obvious advantage than that of inorganic cathodes. In addition to carbonyl active centers of CO, Niu's group also reported diquinoxalino [2,3-a:2′,3′-c] phenazine (HATN) cathode with Organic cathode materials with redox-active sites and flexible structure are promising for developing aqueous zinc ion batteries with high capacity and large output power. However, the energy storage of most organic hosts relies on the coordination/incoordination reaction between Zn 2+ /H + and a single functional group, which result in inferior capacity, low discharge platform, and structural instability. Here, the lead is ...

Enabling Multi-Chemisorption Sites on Carbon Nanofibers Cathodes by an In-situ Exfoliation Strategy for High-Performance Zn–Ion Hybrid Capacitors

“…Figure 3 e displayed the ex-situ O 1 s spectra of the N-OPCNF electrode. During the discharge, the ratio of the characteristic peaks corresponding to the carbonyl group (531.3 eV) decreased continuously, and a new peak at 532.1 eV corresponding to the C–O–Zn bond was detected [ 15 , 49 ]. During the charging process, a reversible increase in the ratio of carbonyl groups was observed, accompanied by the gradual disappearance of the C–O–Zn peak, which indicated that a reversible pseudocapacitance reaction occurred between the Zn 2+ and the carbonyl groups on the surface of the carbon nanofibers [ 41 , 50 ].…”

Design Strategies for High‐Energy‐Density Aqueous Zinc Batteries

“…[19] Furthermore, the hierarchical configuration of poly(1,5-naphthalenediamine,1 ,5-NAPD) and poly(para-aminophenol, pAP) on nanoporous carbon can facilitate the complete activation of the coordination centers (C=Oand C=N) for Zn 2+ . [20] On the other hand, despite the high theoretical capacity of small organic compounds such as benzoquinone (BQ), their electrochemical stability is poor due to the lack of sufficient covalent structure.T herefore,s imply pursuing high capacity in coordination-type organic compounds may be counterproductive.T he aim is to achieve ag ood balance between structure (carbon skeleton and active groups) and electrochemical performance (cycling stability and capacity).…”

Conducting polymers with redox active pendant groups: their application progress as organic electrode materials for rechargeable batteries

“…Zhao et al 173 attempted to introduce multiple redox centres into organic composite materials to solve the problem of low capacity due to over-reliance on cations reacting only with a single functional group in zinc batteries. They first electrodeposited poly(1,5-naphthalenediamine, 1,5-NAPD) in situ on nanoporous carbon as the stable intermediate layer and then daubed poly( para -aminophenol, pAP) skin on top of 1,5-NAPD as an external conducting layer.…”