Self-Template Synthesis of Nickel Cobalt Sulfide Hollow Nanotubes for High-Performance Battery-Type Supercapacitors
Miao Wang, Lulu An, Mengmeng Wu, Shuaiguo Zhang, Yu Feng, Xiaodan Zhang, Jie Mi
Abstract
In this work, nickel cobalt sulfide with hollow tubular structure was synthesized by solvothermal and subsequently anion-exchange processes. The nickel cobalt sulfide nanotubes processed high specific capacity (531.9 C g −1 at 0.5 A g −1 ) when it directly used as electrode material. Furthermore, an asymmetric supercapacitor was fabricated with nickel cobalt sulfide nanotubes as a positive electrode and active carbon as a negative electrode. The asymmetric device exhibited a maximum energy density of 25.7 Wh kg −1 and a maximum power density of 4315 W kg −1 , and excellent cycling performance (84.3% capacity retention) over 10000 cycles. The excellent electrochemical behaviors indicated that nickel cobalt sulfide nanotubes were highly desirable for high capacity energy storage devices.