Bipolar Supercapacitive Performance of N-Containing Carbon Materials Derived from Covalent Triazine-Based Framework

ChemSusChem. 2024 Sep 3:e202401716. doi: 10.1002/cssc.202401716. Online ahead of print.

Abstract

The search for new electrode materials for bipolar-supercapacitor performance is the intention of numerous research in the area of functional framework materials. Among various electrode materials, covalent triazine-based frameworks (CTFs) are in the spotlight drawing much attention as potential electrode material for energy storage owing to their tunable surface area, pore size distribution, and heteroatom content. Herein, we present the synthesis of nitrogen-functionalized CTFs marked as CTF-Py-600 and CTF-Py-700 with high nitrogen content (18 % and 14 %, respectively) for supercapacitor application by applying the 2,6-dicyanopyridine monomer via the polymerization reaction under ionothermal condition. The BET surface areas of these materials are in the range of 940-1999 m2 g-1. CTF-Py-700 demonstrates outstanding electrochemical performance in both potential windows. At the negative potential window, it exhibits a higher specific capacitance of 435 F g-1 (at 1 A g-1) compared to the positive potential window, where it shows a specific capacitance of 306 F g-1 (at 1 A g-1) owing to the synergistic existence of its large surface area (1999 m2 g-1) and high nitrogen content (14 %) with inherent microporosity. Remarkable cycling stability without noticeable degradation of specific capacitance after 15000 cycles was recorded for CTF-Py-700. This suggests that the nitrogen-functionalized CTFs are going to be a highly demanded electrode material for electrochemical energy storage applications.

Keywords: Bipolar supercapacitor; Covalent triazine-based frameworks (CTFs); Energy storage; Porous materials.