05.08.17.Chemists make laser-induced graphene from wood.
Rice University scientists have made wood into an electrical conductor by turning its surface into graphene.
Rice chemist James Tour and his colleagues used a laser to blacken a thin film pattern onto a block of pine. The pattern is laser-induced graphene (LIG), a form of the atom-thin carbon material discovered at Rice in 2014.
"It's a union of the archaic with the newest nanomaterial into a single composite structure," Tour said.
The discovery is detailed this month in Advanced Materials.
Previous iterations of LIG were made by heating the surface of a sheet of polyimide, an inexpensive plastic, with a laser. Rather than a flat sheet of hexagonal carbon atoms, LIG is a foam of graphene sheets with one edge attached to the underlying surface and chemically active edges exposed to the air.
Not just any polyimide would produce LIG, and some woods are preferred over others, Tour said. The research team led by Rice graduate students Ruquan Ye and Yieu Chyan tried birch and oak, but found that pine's cross-linked lignocellulose structure made it better for the production of high-quality graphene than woods with a lower lignin content. Lignin is the complex organic polymer that forms rigid cell walls in wood.
Source : Rice University