Metallic Co: A promising electrode materials to boost electrochemical performances of Co3O4 for energy storage

Polymer materials and inorganic non-metallic materials have been extensively investigated as electrode materials, but there is very little research on metal materials. Herein, we report a simple NH3-induced reduction process to synthesize metallic Co nanoparticles, and explore them as electrode materials for supercapacitors for the first time. The metallic Co presents a specific capacity of 80C g(-1) (209F g(-1)) at 0.5 Ag-1, higher than the 40C g(-1) (105F g(-1)) of Co3O4. And the capacity retention is 114% after 10,000 cycles. Besides, the as assembled metallic Co//activated carbon hybrid supercapacitor can achieve the maximum energy density of 12.8 W h kg(-1) at 197.1 W kg(-1).

Automated summary

A simple NH3-induced reduction process was reported to synthesize metallic Co nanoparticles, which were explored as electrode materials for supercapacitors for the first time. The metallic Co exhibited a high specific capacity and excellent capacity retention after a large number of cycles. The hybrid supercapacitor of metallic Co//activated carbon achieved a high energy density at a relatively high power density.