Self‐Assembly Construction of Carbon Nanotube Network‐Threaded Tetrathiafulvalene‐Bridging Covalent Organic Framework Composite Anodes for High‐Performance Hybrid Lithium‐Ion Capacitors

Abstract

Hybrid lithium‐ion capacitors (HLICs), a special class of electrochemical energy storage devices composed of battery‐type anodes and capacitor‐type cathodes, have the potential to bridge the gap between high‐energy‐density batteries and high‐power‐density capacitors. Nevertheless, the key challenge for developing high‐performance HLICs is the imbalances of the electrochemical kinetics and lifespans between the battery‐type anodes and capacitor‐type cathodes. Herein, the self‐assembly preparation of the 3D‐crosslinked carbon nanotube (CNT) network‐threaded tetrathiafulvalene‐bridging covalent organic framework (TTF‐COF) composite via in situ growth of the 2D‐stacked TTF‐COF capping layer alongside the outer walls of 3D‐interlaced CNTs is reported. Originated for the electron‐donating and redox‐switchable TTF units, the TTF‐COF component has abundant active sites and high charge conductivity for reversible Li+ storage. Moreover, due to the 3D‐assembled architecture, the TTF‐COF/CNT composite possesses abundant open nanochannels for ion transfer and 3D‐interconnected conductive CNT network for electron transfer. When used in HLICs, the TTF‐COF/CNT composite anodes exhibit ultrahigh specific capacity (609 mAh g−1 at 100 mA g−1) and outstanding power density (12 000 W kg−1 at 4000 mA g−1). Herein, the design of advanced COF composite materials with high activity, porosity, and conductivity can be a promising route for boosting the overall performances of high‐power‐type energy storage devices.

Biomass‐Derived Carbon‐Based Multicomponent Integration Catalysts for Electrochemical Water Splitting

“…Carbon sources can be classified into inorganic/hybrid carbon sources (carbide, [38][39][40][41] graphene, [42][43][44][45] carbon nanotube [46][47][48] or metal-organic frameworks (MOFs), [49][50][51][52][53] etc.) and pure organic carbon sources, such as amines, [54,55] covalent organic frameworks (COFs), [56][57][58] alkanes and porous organic polymers (POPs) and so on. [59,60] It is worth noting that inorganic/hybrid carbon sources are advantageous for that they can be accurately compounded with various heteroatoms or metals, for example carbon-based MICs can be fabricated using MOFs even without the addition of post-synthetic metals or heteroatoms.…”

A Cost‐Effective Production Route of Li4Ti5O12 Resisting Unsettled Market and Subsequent Application in the Li‐Ion Capacitor

“…[ 16–18 ] Their quick surface redox reaction mechanism allows for more energy storage, bringing the device a higher energy density than EDLCs. Due to the distinct mechanisms/classifications of the two electrodes, these devices are referred to as “asymmetric supercapacitors” or “hybrid supercapacitors.” [ 17,19,20 ] Moving forward by substituting a LIB electrode for one EDLC electrode in the asymmetric supercapacitors, [ 21–23 ] the obtained device's energy density should be improved remarkably due to the much higher specific capacity of the LIB's active material [ 24,25 ] . This device's power density and cyclic life should also be superior to LIBs due to the similar synergistic effect.…”

Electrochemical analysis of asymmetric supercapacitors based on BiCoO3@g-C3N4 nanocomposites

“…5 Among different energy storage systems, batteries and supercapacitors (SCs) or electrochemical capacitors are significant. 6,7 SCs have high power density, fast charging, and high cycle stability better than batteries. It is a very excellent support system for batteries and is mostly used in electrical vehicles, braking systems, smart grids, small electronic gadgets, and air crafts, etc.…”