Facile fabrication of comb-like porous NiCo2O4 nanoneedles on Ni foam as an advanced electrode for high-performance supercapacitor

Abstract

It is very desirable to develop the high-performance supercapacitors to meet the rapidly growing demands for energy-autonomous operation and miniaturization of devices. Herein, comb-like porous NiCo2O4 nanoneedles on the three-dimension (3D) nickel foam (NF) have been successfully synthesized through a facile pulsed laser ablation (PLA) approach without any post-treatments and surfactant (denoted as NiCo2O4-PLA). The influence of working solution during the fabricated process on the properties of NiCo2O4-PLA has been demonstrated in detail in terms of the crystalline structure, specific surface area, morphology, and electrochemical performance. Benefiting from the large specific surface (261.4 m2 g−1), abundant pores, and highly conductive scaffold, the NiCo2O4-PLA binder-free electrode exhibits an outstanding specific capacitance (1650 F g−1 at a current density of 1 A g−1) and eminent cycling performance (91.78% retention after a 12,000-cycle test at a current density of 10 A g−1) compared with the control samples. The assembled asymmetric device (NiCo2O4-PLA//AC-ASCs) delivers the high specific capacitance of 126.9 F g−1 at the current density of 1 A g−1, the large energy density of 56.7 Wh kg−1 at a power density of 756 W kg−1, and the low internal resistance. The attractive results strongly prove that it is an ideal candidate for advanced supercapacitor application.