Advances in electrochemical energy storage with covalent organic frameworks

Abstract

The use of all-organic materials for electrochemical energy storage holds great promise for the development of foldable cellphones, lightweight computers, stretchable patch-type electronic devices, and other technologically advanced applications. Thus,...

Ultralarge Free‐Standing Imine‐Based Covalent Organic Framework Membranes Fabricated via Compression

“…In addition, COFs allow accurate and predictable control over composition, topology, and porosity. In this context, imine‐based COFs are an excellent choice for many applications [ 11 ] since they can also be processed into different macroscopic morphologies, including foams, aerogels, and membranes. [ 12 ]…”

“…Before this work, several methods have been developed to fabricate COFs and COF‐based membranes, which have already demonstrated remarkable applications in catalysis and separation processes. [ 11c ] Some of the most common fabrication methods include COF blending into polymer matrices to form mixed‐matrix membranes (MMMs) [ 13 ] and the in situ growth method. [ 14 ] Recently, new ways have been reported to produce continuous COF‐membranes, either on surfaces or free‐standing.…”

Covalent Organic Framework for Rechargeable Batteries: Mechanisms and Properties of Ionic Conduction

“…COFs, possessing well‐defined pore structure, low density, large surface area, desired chemical motifs, and excellent stability, have achieved great successes in the rechargeable battery application. [ 3,22,23,44–49,120–130 ] Moreover, the emerging ion‐conducting COFs with excellent ionic conductivity and high cation transfer number can reduce the battery polarization and improve the charging/discharging kinetics of electrodes. [ 131–143 ] The distinctive directional selectivity of ionic conduction in COFs is obviously different from the typical inorganic solid conductors and polymer conductors, so that COFs are suitable for diverse battery applications, including lithium‐ion, [ 144–166 ] lithium–sulfur, [ 167–208 ] sodium‐ion, [ 209–214 ] potassium‐ion, [ 215–219 ] lithium–CO 2 , [ 220–223 ] zinc‐ion, [ 224–230 ] zinc–air batteries, [ …”

π-Conjugated redox-active two-dimensional polymers as organic cathode materials

“…[1][2][3] Redox-active twodimensional polymers (RA-2DPs, also referred to as covalent organic frameworks 4,5 ) are among the most promising candidates as faradaic charge storage materials because of their tailored topologies and resultant regular porosities. [6][7][8][9][10][11][12] However, RA-2DPs have not reached their potential because the typical structures exhibit poor electrical conductivity 13,14 and their electro-inactive solubilizing moieties reduce the gravimetric energy storage performance. 15 This realization has led researchers to explore incorporating conducting additives [16][17][18] and exfoliating 2DPs into the few-layer limit 19 with the goal of increasing electrochemical accessibility.…”

“…While these investigations demonstrate that increased electrochemical accessibility can improve faradaic performance in RA-2DPs, these strategies require laborious post-processing, expensive substrates and valuable additives. More importantly, the mass-loading of active materials in those devices is generally low 9 due to poor intrinsic electrical conductivity, which limits their deployment in practical devices.…”