One of the major limitations in electronic applications of covalent organic frameworks (COFs) is the structural disorder and low degree of π-conjugated. These structural defects cause low electrochemical accessibility of the redox-active sites, and thereby, lower electrical conductivity and lower energy storage. In this poster, we present the synthesis and performance of crystalline Aza-COF in sodium-ion batteries. The insoluble Aza-COF based-electrode in ether-based electrolyte exhibits a remarkably high average specific capacity of 550 mA h g<sup>-1</sup> at a current rate of 0.1 C. This superior capacity delivery is attributed to a swift surface-controlled Faradic process as well as Na<sup>+</sup> diffusion-controlled process, which is a combination of pseudocapacitive and battery behaviors. This behavior combination is essential to obtain high energy density and high-power density. Aza-COF based-electrode exhibits an outstanding rate capability at different current densities. Furthermore, the electrode performed cycling stability after 500 cycles with capacity retentions of 87% and coulombic efficiencies of almost unity.

Redox-active covalent organic frameworks for sodium-ion storage in high energy density sodium-ion batteries

ACS Fall 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.