Nitrogen-Doped Porous Carbon Derived from Carbazole-Substituted Tetraphenylethylene-Based Hypercrosslinked Polymer for High-Performance Supercapacitor

摘要

Nitrogen-doped porous carbons are synthesized by KOH activation of hypercrosslinked 1,1,2,2-tetrakis (4-(9H-carbazol-9- yl)phenyl)ethene (HTCP) polymer for efficient supercapacitor application. The obtained materials possess combined microporous and mesoporous structures with high BET surface area of upto 2226 m~2 g~(-1) and nitrogen content of upto 2.62%. These structural properties result in increased accessible surface and redox sites for enhanced electrochemical capacitive storage. Effects of nitrogen functionalities and carbonization temperature on the porous materials are studied by monitoring the capacitive behaviours of the samples. The material afforded by carbonization of HTCP at 700°C (HTCP-700) offers a high specific capacitance of 445 F g~(-1) (1 A g~(-1)) and excellent cycle durability of nearly 100% retention upto 10000 cycles in 1 M H2SO4 electrolyte. The cyclic voltammetry and galvanostatic charge-discharge experiments indicate a good rate capability (278 F g~(-1) at 20 A g~(-1)). The supercapacitor device fabricated with PVA-H2SO4 gel electrolyte using HTCP-700 as an active material delivered maximum energy density of 11.6 W h kg~(-1).