Covalent triazine frameworks for advanced energy storage: challenges and new opportunities

Abstract

In comparison to inorganic electrode materials utilised in energy storage systems, organic electrode materials possess several advantages, including a lightweight nature, customisable structure, high specific capacity, wide availability of natural resources, and recyclability. However, the low ionic conductivity and susceptibility to degradation over time result in inferior performance and a shorter lifespan when compared to inorganic electrode materials. Recently, covalent triazine frameworks (CTFs) have emerged as a promising strategy for the development of organic electrodes. CTFs are a type of covalent organic framework that exhibit customisable porosity, modifiable structures, and versatile functionality. They are characterised by a rigid triazine (C₃N₃) linking unit, which affords excellent thermal and chemical stability, enabling them to resist structural deformation upon cycling. CTFs have garnered considerable attention for their potential to store and transport charges in various electrochemical energy storage devices over the past few years. This review provides a comprehensive overview of the working principle and synthesis methods of CTFs, highlighting the significant advances in supercapacitors and various rechargeable battery systems. Additionally, this review introduces different design strategies and potential impacts on improving electrochemical performance. Finally, this review concludes by highlighting the opportunities for future research in this rapidly advancing field.