Supramolecular Engineering of Cathode Materials for Aqueous Zinc‐ion Energy Storage Devices: Novel Benzothiadiazole Functionalized Two‐Dimensional Olefin‐Linked COFs

Abstract

Two-dimensional covalent organic frameworks (COFs) have emerged as promising materials for energy storage applications exhibiting enhanced electrochemical performance. While most of the reported organic cathode materials for zinc-ion batteries use carbonyl groups as electrochemically-active sites, their high hydrophilicity in aqueous electrolytes represents a critical drawback. Herein, we report a novel and structurally robust olefin-linked COF-TMT-BT synthesized via the aldol condensation between 2,4,6-trimethyl-1,3,5-triazine (TMT) and 4,4'-(benzothiadiazole-4,7diyl)dibenzaldehyde (BT), where benzothiadiazole units are explored as novel electrochemically-active groups. Our COF-TMT-BT exhibits an outstanding Zn 2 + storage capability, delivering a state-of-the-art capacity of 283.5 mAh g À 1 at 0.1 A g À 1 . Computational and experimental analyses reveal that the charge-storage mechanism in COF-TMT-BT electrodes is based on the supramolecularly engineered and reversible Zn 2 + coordination by the benzothiadiazole units.

Ultralong-Life Quinone-Based Porous Organic Polymer Cathode for High-Performance Aqueous Zinc-Ion Batteries

“…(e) Electrochemical performance (cycle number and capacity retention) comparison of the rPOP with previously reported organic cathodes for aqueous ZIBs. The inset shows the comparison plot of the energy density of rPOP at 0.1 A g –1 [HAQ-COF, TABQ, COF-TMT-BT, BT-PTO-COF, PANI, PPPA-COF, PTA-026, PAF-205/CNT, DADB, PDA].…”

“…The dissolution of the rPOP electrode was tested by immersing the pristine, the discharged (0.1 V), and the charged (1.6 V) electrodes in 1 M ZnSO 4 electrolyte for 36 h. As depicted in Figure S15, the rPOP remained insoluble in the electrolyte even in a completely discharged state (0.1 V). rPOP 60 TABQ, 22 COF-TMT-BT, 63 BT-PTO-COF, 58 PANI, 64 PPPA-COF, 61 PTA-026, 65 PAF-205/CNT, 66 DADB, 67 cathodes have high electrochemical stability in rechargeable aqueous batteries.…”

A critical review on emerging photoactive porous materials for sulfide oxidation and sulfur mustard decontamination

“…On the other hand, COFs offer a unique platform for studies associated with organic π-conjugated systems, where the micro-confined spaces inside a porous framework can trigger various interactions to produce excitons, ions, spins, and other excited molecular species. 78 From the point of view of practical implementation COFs can be used for various applications like selective gas uptake, 79 heterogeneous catalysis, 80 molecular separations, 81 proton conduction, 82 carbon dioxide (CO 2 ) capture, 83 conversion 84 and energy storage, 85 etc . This article emphasises the recent advancement of COFs as photocatalysts to produce reactive oxygen species (ROS) like 1 O 2 or O 2 ˙ − via O 2 activation HD decontamination.…”

Covalent Organic Frameworks as Promising Electrode Materials for High-Valent Ion Rechargeable Batteries

“…(e) Synthesis process, (f) charge–discharge profiles, and (g) simulated density of states and band structures of COF-TMT-BT. Reprinted with permission from ref . Copyright 2023 The Authors.…”

“…In addition to raising the number of active sites per unit area, the development of new active sites offers better prospects for the structural design of COFs. Recently, Peng et al 34 explored COF-TMT-BT containing new active benzothiadiazole units based on the design of introducing highly electronegative atoms (N and S) in the carbon skeleton. COF-TMT-BT is obtained by the aldehyde condensation reaction between 2,4,6trimethyl-1,3,5-triazine (TMT) and 4,4′-(benzothiadiazole-4,7diyl)dibenzaldehyde (BT) (Figure 2e).…”