Construction of Anthraquinone-Containing Covalent Organic Frameworks/Graphene Hybrid Films for a Flexible High-Performance Microsupercapacitor

Abstract

The porous structural backbone and redox-active of covalent organic frameworks can facilitate the evolution of energy storage equipment with high electrochemical performances. However, the application of covalent organic frameworks as supercapacitor electrode materials in advanced energy storage equipment has been hindered on account of the insufficient conductivity and consecutive impoverished electrochemical performances. Here we give an account of an efficacious method for improving the electrical conductivity of anthraquinonecontaining covalent organic frameworks (COFs) by incorporating reduced graphene oxide (rGO) sheets into the COF. Benefiting from the in situ synthesis of the COF along the surface of the twodimensional rGO nanosheets, the obtained COF@rGO hybrid films possess important intermolecular π−π interaction between rGO nanosheets and the COF. Meanwhile, the presence of the COF can avoid accumulation of rGO nanosheets, thereby achieving effective electrolyte ion transportation. Therefore, the optimal COF@rGO film possesses a good specific capacitance of 451.96 F g −1 , showing breakthrough within COF-based electrodes. In addition, the assembled planar COF@rGO microsupercapacitor (COF@ rGO-MSC) delivers a large stable electrochemical window (2.5 V), a good energy density (44.22 W h kg −1 ), and an excellent structural stability.

Covalent Organic Frameworks for Capacitive Energy Storage: Recent Progress and Technological Challenges

“…Using an arbitrary filtering mask, comb‐shaped electrodes were obtained and used to fabricate flexible micro‐supercapacitors (Figure 5f), delivering a maximum power density of 9998 W kg −1 . [ 65 ]…”

“…Using an arbitrary filtering mask, comb-shaped electrodes were obtained and used to fabricate flexible microsupercapacitors (Figure 5f), delivering a maximum power density of 9998 W kg −1 . [65] 3D porous substrates, such as graphene aerogels and other carbon skeletons, were also used to assemble hybrids with in situ synthesized COFs. 3D carbon substrates usually possess abundant and interconnected macropores with large pore sizes, allowing easy infiltration of COF monomers.…”

Covalent Organic Frameworks (COFs)/MXenes Heterostructures for Electrochemical Energy Storage

“…However, with a few exceptions, 2D COFs are often prepared in insoluble powder forms, which largely restrict the hassle-free flow of carrying ions, electrical conductivity, and charge transfer. Hence, a common strategy is to use COFs with conductive material like graphene, − CNT, − conductive polymers, , etc., which increases COFs’ conductivity significantly by proper alignment of π building units in the 2D layers. , …”

Integrated carbon nanotube and triazine-based covalent organic framework composites for high capacitance performance

“…Because of their high power density, wide temperature range, long life, fast charging speed, green environmental protection and other characteristics, supercapacitors have a wide range of applications in various fields. 1–5 As portable electronic products are becoming increasingly commonplace in daily life, the development of an efficient electrochemical capacitor with the advantages of ultra-thin structures, flexibility, lightweight and eco-friendly nature has become one of the current research hotspots. According to their principle of action, supercapacitors are divided into two categories, namely pseudo-supercapacitors and electrochemical double-layer capacitors (EDLCs).…”