Synthesis of three-dimensional multifunctional Co3O4 nanostructures for electrochemical supercapacitors and H2 production

Co3O4 nanomaterials are grown in situ on nickel foam by a facile two-step method, and their electrochemical properties for supercapacitors and electrochemical H-2 production are systematically investigated. As an electrode material for supercapacitors, the Co3O4/NF nanomaterials have a specific capacitance of 4705 mF/cm(2) at a current density of 2.5 mA/cm(2) in 6 M KOH solution with good cycling stability. The asymmetric supercapacitor assembled with Co3O4/NF (positive) and activated carbon (negative) exhibits high energy storage capacity (2023 mF/cm(2) at 5 mA/cm(2)), good rate performance and cycling stability. In addition, the Co3O4/NF nanocomposites exhibit excellent catalytic performance in electrolytic aquatic hydrogen. In 1 M KOH electrolyte, a potential of only 225 mV is required to provide a current density of 30 mA/cm(2). Furthermore, increasing the temperature enhances the catalytic performance of the material, which provides the possibility of using industrial production waste heat to catalyze hydrogen production. Therefore, this study not only shows the great potential of Co3O4/NF nanocomposites as a supercapacitor cathode material, but also indicates its great opportunity for hydrogen production.

Automated summary

In this study, Co3O4 nanomaterials were synthesized on nickel foam using a simple method, and their electrochemical properties for supercapacitors and electrochemical hydrogen production were investigated. The Co3O4/NF nanomaterials showed high specific capacitance and cycling stability as electrode materials for supercapacitors, and exhibited excellent catalytic performance in electrolytic hydrogen production.