2D Nanosheets /3D Cubic Frameworks Ni-Co Sulfides for Improved Supercapacitors Performance via Structurally Engineering
The construction of multi-dimensional structured battery-type electrode materials is a promising strategy to develop high performance electrodes for supercapacitors. Herein, a series of battery-type Ni3S2@Co3S4 electrodes with different morphologies are synthesized by controlling the hydrothermal reaction time. Owning to the unique structure with independent but interconnected 2D nanosheets and 3D cubic frameworks, NCS-60 displays high conductivity, rich active sites and good wettability behaviors. It can deliver a high specific capacity of 388.9 mAh g-1 (3500 F g-1) at 1 A g-1, outstanding rate capacity of keeping 88.6% at 10 A g-1 and long cycle stability. The battery-type supercapacitors hybrid (BSH) device with active carbon (AC) as the negative electrode delivers energy density of 41.8 W h kg-1 at the power density of 800 W kg-1. This work provides a feasible route for regulating morphologies of in-situ growth materials and then improves the electrochemical performance for supercapacitors.