Ultrastrong, Chemically Resistant Reduced Graphene Oxide-based Multilayer Thin Films with Damage Detection Capability

Area of Science:

• Materials Science
• Polymer Science
• Nanotechnology

Background:

• Layer-by-layer assembly is a versatile technique for creating multilayer thin films.
• Graphene oxide (GO) and poly(vinylamine) (PVAm) are functional materials with potential applications in composites.
• Controlling film properties at the nanoscale is crucial for advanced material development.

Purpose of the Study:

• To fabricate and characterize multilayer thin films of graphene oxide (GO) and poly(vinylamine) (PVAm).
• To investigate the effect of pH on film thickness, GO spacing, and GO concentration.
• To evaluate the electrical conductivity, mechanical properties, and chemical resistance of the developed films.

Main Methods:

• Layer-by-layer assembly of graphene oxide (GO) and poly(vinylamine) (PVAm).
• pH adjustment to control film thickness, GO spacing, and GO concentration.
• Thermal reduction to impart electrical conductivity.
• Cross-linking with glutaraldehyde to enhance chemical resistance.

Main Results:

• PVAm pH effectively controlled film thickness and GO layer spacing.
• Thermal reduction yielded electrically conductive PVAm/GO films with tunable conductivity.
• The reduced films demonstrated exceptional elastic modulus (30 GPa) and hardness (1.8 GPa).
• Cross-linking enhanced chemical resistance to acidic and salty solutions.
• Film damage was detectable via electrical resistance changes.

Conclusions:

• Multilayer PVAm/GO films can be fabricated with tunable properties using layer-by-layer assembly and pH control.
• The thermally reduced films possess outstanding mechanical properties, surpassing many reported graphene-polymer composites.
• These materials offer integrated damage detection capabilities.
• The developed films show significant promise for advanced packaging and electronic applications.