NiCo₂O₄@Porous Graphene Aerogel: Synergistic Adsorption-Catalysis for Enhancing Polysulfide Conversion

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Lithium-sulfur batteries (LSBs) face challenges in commercialization due to polysulfide shuttling.
• Transition metal oxides and porous carbon materials offer synergistic effects for LSBs.

Purpose of the Study:

• To develop a hierarchical NiCo2O4@rGA material for accelerated catalytic conversion of polysulfides in LSBs.
• To investigate the influence of NiCo2O4 loading on the electrochemical performance of LSBs.

Main Methods:

• A cogrowth strategy was employed to anchor NiCo2O4 onto a reduced graphene oxide aerogel (rGA).
• The synthesized NiCo2O4@rGA material was characterized for its surface area and electrochemical properties.
• In situ UV-vis spectroscopy was used to confirm the catalytic conversion of polysulfides.

Main Results:

• The NiCo2O4@rGA material exhibited a higher specific surface area (226 m2 g-1) compared to rGA (133 m2 g-1).
• The NCO@rGA-13/S cathode delivered an initial discharge specific capacity of 1112 mAh g-1 at 1 C, retaining 722 mAh g-1 after 500 cycles.
• In situ UV-vis spectroscopy confirmed accelerated polysulfide conversion with NiCo2O4@rGA.

Conclusions:

• The hierarchical NiCo2O4@rGA material effectively promotes dual adsorption and catalytic conversion of polysulfides.
• This strategy is conducive to improving the cyclic performance and facilitating the industrialization of LSBs.