Hemispherical flower-like N-doped porous carbon/NiCo2O4 hybrid electrode for supercapacitors

The N-doped porous carbon/NiCo 2 O 4 (NPC/NiCo 2 O 4 ) substance is designed and synthesized via hydrothermal treatment , polymerization, carbonization , activation, and chemical bath deposition. The as-prepared NPC/NiCo 2 O 4 holds hemispherical flower-like structure that consists of two things: a porous bowl-shaped NPC at the inside, and sheet NiCo 2 O 4 at the whole outside, in which NPC works as a scaffold for NiCo 2 O 4 to restrain NiCo 2 O 4 nanosheets from aggregation in the synthesis process and NiCo 2 O 4 acts as a capacitive coating layer, and causing a synergic effect. The composite electrode has a specific capacitance of 948.30 F g −1 at a current density of 1 A g −1 , enhanced rate capability (727.43 F g −1 at 16 A g −1 ) and good conductivity. Additionally, NPC/NiCo 2 O 4 reaches a desirable cycling stability (87.4% capacitance retention after 2000 cycles even at a high current density of 10 A g −1 ), suggesting a hopeful electrode material for the electrochemical supercapacitors .