Well-Adhered Copper Nanocubes on Electrospun Polymeric Fibers.

Area of Science:

• Materials Science
• Nanotechnology
• Polymer Science

Background:

• Electrospun polymer fibers serve as templates for metallic nanostructures.
• Weak interfacial adhesion is a common challenge between metallic species and polymer macromolecules.

Purpose of the Study:

• Investigate the adhesion of copper nanocubes on chemically treated aligned electrospun polyacrylonitrile (PAN) fibers.
• Understand adhesion mechanisms under mechanical deformation and strain.

Main Methods:

• Subjecting composite structures (copper nanocubes on PAN fibers) to tensile strain levels (7%, 11%, 14%).
• Analyzing fiber deformation behaviors (necking, dilatation, craze formation) using microscopy.
• Employing Raman spectroscopy to identify adhesion mechanisms.
• Estimating interfacial adhesion energy using Gibbs-Wulff-Kaischew shape theory.

Main Results:

• Copper nanocubes demonstrated strong adhesion on both nanofibers and microfibers across all tested strain levels.
• Distinct deformation mechanisms were observed based on fiber size: nanofibers showed necking, while microfibers exhibited dilatation and craze formation.
• Raman spectroscopy indicated chemisorption as the primary adhesion mechanism.
• Interfacial adhesion energy was approximated at 1 J/m², with a lower bound of 0.48 J/m².

Conclusions:

• Chemically treated PAN fibers provide a robust substrate for stabilizing metallic nanostructures like copper nanocubes.
• Mechanical strain can be utilized to probe and quantify interfacial adhesion in polymer-nanoparticle composites.
• The findings offer insights into designing advanced composite materials with enhanced interfacial properties.