Facile stepwise hydrothermal synthesis of hierarchical CoMoO4/CoMoO4 core/shell dandelion-like nanoarrays: A promising binder-free positive electrode for high-performance asymmetric supercapacitors

In this study, we have fabricated a flexible supercapacitor with outstanding pseudocapacitive performance using hierarchical CoMoO4/CoMoO4 core/shell dandelion-like nanoarrays. The dandelion-like CoMoO4/CoMoO4 nanostructure electrode yields a high specific capacitance (1548 F g(-1) at a current density of 1 A g(-1)) and superior cycling stability performance (94% capability retention after 5000 cycles at 8 A g(-1)) in the 3 mol L-1 KOH solution. Furthermore, a flexible asymmetric supercapacitor device was assembled based on nickel foam/CoMoO4/CoMoO4 dandelion-like as positive electrode and activated carbon (AC) as negative electrode. The CoMoO4/CoMoO4 nanostructure//AC asymmetric supercapacitor device represents remarkable electrochemical performance such as good specific capacitance of 152 F g(-1) and maximum energy and power densities of 54.04 Wh kg(-1) and 8.83 kW kg(-1), respectively. These encouraging results depict great potential in developing energy storage devices by making heterostructure nanomaterials.

Automated summary

This study successfully fabricated a flexible supercapacitor with outstanding pseudocapacitive performance using hierarchical CoMoO4/CoMoO4 core/shell dandelion-like nanoarrays. The flexible asymmetric supercapacitor device assembled based on this material exhibited remarkable electrochemical performance, including good specific capacitance and high energy and power densities. These results indicate great potential for developing energy storage devices using heterostructure nanomaterials.