Nanostructured copper/copper oxide hybrids: combined experimental and theoretical studies

Area of Science:

• Materials Science
• Electrochemistry
• Computational Materials Science

Background:

• Copper oxides are crucial for catalysis and energy applications.
• Dealloying of aluminum-copper alloys offers a route to nanostructured materials.

Purpose of the Study:

• To investigate the oxidation mechanisms of copper in aqueous electrolytes during the dealloying of sintered Al85Cu15 alloys.
• To characterize the resulting nanostructured copper/copper oxide hybrids.

Main Methods:

• Preparation of nanostructured copper/copper oxide hybrids via dealloying of sintered Al85Cu15 alloy.
• Molecular dynamics (MD) simulations and density functional theory (DFT) calculations.
• Microstructural and morphological characterization using XRD, SEM, and TEM.

Main Results:

• Cu/Cu2O/CuO compositions formed in NaOH solution.
• Sintered Al85Cu15 alloy exhibits inhomogeneous atom distribution, unlike cast alloys.
• DFT revealed higher surface energies for copper clusters and stronger binding with oxygen, favoring oxide nucleation.
• CuO formed as nanoplates, Cu2O as nanoparticles, and nanoporous copper (NPC) showed a bicontinuous structure.

Conclusions:

• The study elucidates copper oxidation mechanisms during dealloying, supported by experimental and theoretical evidence.
• Inhomogeneous atom distribution and cluster behavior influence oxide formation.
• The findings contribute to understanding dealloying processes for advanced material design.