Co3O4@Co3S4 core-shell neuroid network for high cycle-stability hybrid-supercapacitors

In hybrid-supercapacitors, battery-type electrode materials usually suffer from their cycle stabilities while pursuing high specific capacities. In order to address the critical issues of cycle stability, advancing materials design is being intensively investigated. Here we present a Co3O4@Co3S4 core-shell neuroid network towards high cycle stability in the hybrid-supercapacitor device. The neuroid network is synthesized by a facile hydrothermal method. In the designed structure, Co3O4 nanowire assembles the nickel foam as the core, and Co3S4 nanosheets grow on the surface of the nanowire as the shell. The monolithic neuroid network integrates the merits from the stability of core and facile conduction channels from the highly active shell, provides the excellent electrochemical performance, especially, well maintaining its structure during cycling. The Co3O4@Co3S4 core-shell neumid electrode provides a maximum specific capacity of 1347 C g(-1) at 1 A g(-1) and a specific capacity retention of 96.6% after 5000 cycles. When assembled into a hybrid-supercapacitor, the neuroid network-based device exhibits an energy density of 44 W h kg(-1) and a power density of 7963 W kg(-1), with a specific capacity retention of 89.5% after 30,000 cycles.

Automated summary

A novel Co3O4@Co3S4 core-shell neuroid network electrode has been designed, which offers excellent electrochemical performance while maintaining high cycle stability. The electrode is able to retain its structure effectively during cycling and has a high specific capacity.