Nickel cobalt sulfide nanosheets uniformly anchored on porous graphitic carbon nitride for supercapacitors with high cycling performance

•A facile hydrothermal route was developed to growth of NiCo2S4 nanosheets uniformly anchored on porous g-C3N4 nanosheets.•NiCo2S4 NSs/P-g-C3N4 shows high specific capacity, outstanding rate capability, and excellent cycling stability.•NiCo2S4 NSs/P-g-C3N4//AC asymmetric supercapacitor delivers high energy density with high cycling performance.

Nickel cobalt sulfide (NiCo2S4) nanosheets were successfully grown on porous graphitic carbon nitride (g-C3N4) nanosheets (NiCo2S4 NSs/P-g-C3N4), which was employed as supercapacitor electrode materials. The NiCo2S4 NSs/P-g-C3N4 electrode shows specific capacity as high as 506 C g−1 at a current density of 1 A g−1, outstanding rate capability and cycling stability (almost no attenuation after 1500 cycles at 3 A g−1), which can be attributed to the unique 'sheets on sheets' architectures providing short ion diffusion pathways, and good ion permeability. NiCo2S4 NSs/P-g-C3N4 was combined with activated carbon (AC) to construct NiCo2S4 NSs/P-g-C3N4//AC asymmetric supercapacitor (ASC), which offers a specific energy of 16.7 W h kg−1 at a specific power of 200 W kg−1, and high cycling performance (about 99% retention after 5000 continuous cycles). An ASC device could power a mini-fan for about 60 s, demonstrating that NiCo2S4 NSs/P-g-C3N4 is a potential electrode material for energy storage.

Graphical abstractA facile hydrothermal route was developed to growth of NiCo2S4 nanosheets uniformly anchored on porous g-C3N4, which shows excellent performance for supercapacitors.Download high-res image (197KB)Download full-size image