g-C3N4 promoted NiFe-LDH self-assemble high performance supercapacitor composites

Provide more active sites and concise preparation is an effective technology in renewable energy storage sets. A soluble graphitic carbon nitride (SCN) nanosheets promoted two-dimensional nano electrochemical activity flake NiFe-LDH is successfully fabricated through electrostatic self-assembly, as a layer by layer high performance electrode (NiFe-LDH@SCN) for supercapacitor. The g-C 3 N 4 guarantees the effectiveness of the combination through the ζ-potential of g-C 3 N 4 flake (−19.5 mV) and NiFe-LDH flake (+15.6 mV), moreover, ensures the exposure of more active sites of NiFe-LDH. The optimized electrode shows an impressive specific capacitance of 1060.4 F g -1 at 1 A g -1 and remains 770.8 F g -1 at 10 A g -1 . The fabricated hybrid supercapacitor (HSC) exhibits a magnificent energy density (up to 68.7 Wh kg -1 ) along with the power density of 827.5 W kg -1 in the wide voltage window of 1.7 V and a prominent long-term stability (83.3 % of capacitance retention even after 8000 cycles). Finally, two HSCs in series can light 40 LEDs. Hence, this work demonstrates the great potential of g-C 3 N 4 in developing high-performance LDH-based energy storage devices. • The high performance electrode (NiFe-LDH@SCN) is fabricated through electrostatic self-assembly. • NiFe-LDH@SCN-32 electrode shows an impressive specific capacitance of 1060.4 F g -1 at 1 A g -1 . • The NiFe-LDH@SCN-32//AC displays a high energy density of 68.7 Wh kg -1 . • The capacitance retention is high up to 83.3 % after 8000 cycles .