Post‐synthetic Modification of Covalent Organic Frameworks through in situ Polymerization of Aniline for Enhanced Capacitive Energy Storage

Abstract Covalent organic frameworks (COFs) having layered architecture with open nanochannels and high specific surface area are promising candidates for energy storage. However, the low electrical conductivity of two‐dimensional COFs often limits their scope in energy storage applications. The conductivity of COFs can be enhanced through post‐synthetic modification with conducting polymers. Herein, we developed polyaniline (PANI) modified triazine‐based COFs via in situ polymerization of aniline within the porous frameworks. The composite materials showed high conductivity of 1.4–1.9×10 −2 S cm −1 at room temperature with a 20‐fold enhancement of the specific capacitance than the pristine frameworks. The fabricated supercapacitor exhibited a high energy density of 24.4 W h kg −1 and a power density of 200 W kg −1 at 0.5 A g −1 current density. Moreover, the device fabricated using the conducting polymer‐triazine COF composite could light up a green light‐emitting diode for 1 min after being charged for 10 s.