Rice University scientists have developed a simple way to produce conductive, three-dimensional (3D) objects made of graphene foam.
The squishy solids look and feel something like a child’s toy but offer new possibilities for energy storage and flexible electronic sensor applications.
The technique detailed in advanced materials is an extension of groundbreaking work by the Tour lab that produced the first laser-induced graphene (LIG) in 2014 by heating inexpensive polyimide plastic sheets with a laser.
The laser burns halfway through the plastic and turns the top into interconnected flakes of two-dimentiosnal (2D) carbon that remain attached to the bottom half. LIG can be made in macroscale patterns at room temperature.
“Now we have built a prototype machine that lets us make graphene foam into 3D objects through automated successive layering and laser exposure,” Tour said. “This truly brings graphene into the third dimension without furnaces or the need for metal catalysts, and our process is easily scaled.”
Rice scientists are making 3D laser-induced graphene (LIG) foam through an automated process that begins by turning the top layer of a polyimide (PI) sheet into graphene (top), stacking another layer on top (center) with ethylene glycol (EG) as a binder and then burning the top layer’s PI into graphene as well (bottom). The process is repeated as necessary. The new method is based on laminated object manufacturing, in which layers of a material are assembled and then cut to shape.