Ultrathin and Porous Ni 3 S 2 /CoNi 2 S 4 3D‐Network Structure for Superhigh Energy Density Asymmetric Supercapacitors

Abstract 3D‐networked, ultrathin, and porous Ni 3 S 2 /CoNi 2 S 4 on Ni foam (NF) is successfully designed and synthesized by a simple sulfidation process from 3D Ni–Co precursors. Interestingly, the edge site‐enriched Ni 3 S 2 /CoNi 2 S 4 /NF 3D‐network is realized by the etching‐like effect of S 2− ions, which made the surfaces of Ni 3 S 2 /CoNi 2 S 4 /NF with a ridge‐like feature. The intriguing structural/compositional/componental advantages endow 3D‐networked‐free‐standing Ni 3 S 2 /CoNi 2 S 4 /NF electrodes better electrochemical performance with specific capacitance of 2435 F g −1 at a current density of 2 A g −1 and an excellent rate capability of 80% at 20 A g −1 . The corresponding asymmetric…

• NN
  National Natural Science Foundation of China

  Awards: 21505050, 51672109