Graphene-Directed Synthesis of Bicontinuous Core/Shell and Tubular Metal Nanostructures for Battery Electrodes

Area of Science:

• Materials Science
• Nanotechnology
• Electrochemistry

Background:

• Nanoporous metals with bicontinuous structures are promising for energy storage and catalysis.
• Limited porosity and structural tunability restrict their widespread application.

Purpose of the Study:

• To develop a graphene-directed strategy for creating hierarchical nanoporous metal architectures.
• To enhance porosity, structural control, and performance in energy storage devices.

Main Methods:

• Controlled oxidation of graphene-coated nanoporous nickel.
• Utilizing a product-layer diffusion-controlled shrinking-core mechanism.
• Fabricating core/shell Ni/NiO and tubular metal nanostructures.

Main Results:

• Achieved tunable core/shell and hollow tubular architectures with up to 86% porosity.
• Demonstrated high reversible capacity (750 mAh g⁻¹) for Ni/NiO in Li-ion batteries.
• Developed a carbon-free Ru cathode for Li-O₂ batteries with high energy efficiency (78%) and over 200 cycles.

Conclusions:

• The graphene-directed method offers a scalable route to engineer functional porous materials.
• Programmable structures and compositions show significant promise for next-generation energy systems.
• This approach overcomes limitations of traditional nanoporous materials for energy applications.