Polymer infiltration and pyrolysis cycling for creating dense, conductive laser-induced graphene

Abstract

Here we show that dense laser-induced graphene (LIG) structures can be synthesized using polymer infiltration and pyrolysis (PIP) cycles, providing a new avenue to polymer-derived carbon structures. LIG is a 3D porous graphene generated through the rapid process of laser writing on a precursor material, in contrast to conventional graphite-to-graphene processes; LIG properties are influenced by the choice of precursor material and the laser parameters such as speed and laser power. PIP has been used to densify composites by back-filling a porous matrix with a liquid Resorcinol Formaldehyde (Res-For) and then pyrolyzing the Res-For to a solid carbon structure. In this study, resorcinol formaldehyde is used as the LIG precursor material; by backfilling the LIG matrix with additional Res-For and lasing again, we demonstrate that the density, conductivity, and mechanical hardness are all increased via a PIP cycling process.