Hybrid electrodes composed of graphitic carbon nitride and zeolitic imidazolate framework‐67 for supercapacitor applications
Sevda Yetiman, Fatma Kılıç Dokan, M. Serdar Önses, Erkan Yılmaz, Ertuğrul Şahmetlioğlu
Abstract
Carbon-based materials with porous and layered forms have irreplaceable worth in renewable energy storage applications, especially after the graphene discovery. Among these materials, graphitic carbon nitride (g-C3N4) shows great promise by including polymeric layers accentuate owing to its cost-effective yet eco-friendly chemistry. Zeolitic imidazolate frameworks (ZIFs) also draw attention to possessing high surface area owing to porous structure. Herein, we present a rational co-synthesis of these materials for the fabrication of high-performance supercapacitors (SCs). G-C3N4@ZIF-67 hybrid electrode demonstrated a high specific capacitance of 657 F g−1 at the current density of 1 A g−1. The specific capacitance of pure g-C3N4 and ZIF-67 were 446 and 560 F g−1 at the same current density. Moreover, the capacitances only decay at 6%, 5%, and 10% after 3500 cycles for g-C3N4, ZIF-67, and g-C3N4@ZIF-67, respectively. The symmetric SC (g-C3N4@ZIF-67//g-C3N4@ZIF-67) also reached the highest specific capacitance of 144 F g−1 at a current density of 0.5 A g−1 and the degradation was 39% after 6000 cycles at a constant current density of 5 A g−1. The presented SC exhibited a maximum energy density of 5.6 Wh kg−1, whereas the power density was as high as 3783 W kg−1. These results mark the obtained g-C3N4@ZIF-67 composite material as a promising electrode candidate for SCs.