Enhancement of electrical conductivity and total yield of laser-inscribed aluminum graphene nanocomposites by multi-layering of polyimide tape

Abstract

Graphene is a single layer of carbon atoms arranged in a two-dimensional hexagonal lattice; it is known for its remarkable electrical and mechanical properties. Further, graphene has the potential to improve the electrical conductivity of substrate metals, such as aluminum, when engraved inside them. This new, highly conductive aluminum-graphene composite material, called a “covetic” material, can thus be used in a variety of industrial applications, from sensors to supercapacitors. This material is fabricated by putting a layer of polyimide (PI) tape over the substrate sample aluminum and applying a laser beam over the surface from a CO₂ laser engraver.  While Ye et al have shown laser-based manufacturing methods to yield high quality, electrically conductive 2D graphene, the question of how to best maximize the total conductivity of the aluminum-graphene nanocomposite remains. This experiment explores one method of increasing bulk conductivity by increasing both the thickness of the PI tape over the aluminum substrate (from the standard 50 µm to 100 µm), as well as the number of times the sample was lased by the engraving machine (ranging from 1 lasing to 5 lasings).