Wood Into Graphite: New Composite Eliminates Heat

Although wood and other cellulose-based materials are predominantly carbon, the carbon atoms are not arranged in any regular order compared to graphite, where carbon atoms organize in hexagonal arrays. To take advantage of graphite's properties, researchers have adapted a technique that converts wood to graphite and retains it's natural honeycomb-like structure.

As modern electronic devices continue to decrease in size, new methods are needed to eliminate heat produced as the devices operate. Graphite-based composites such as the ones under development in this research are especially attractive for managing heat flow. These materials are also lightweight and malleable. Wood, as the graphite source, also adds value because it is a renewable resource.

Unlike petroleum-based materials, wood-based materials do not lend themselves to graphite formation, even at very high temperatures. However, using a liquid nickel catalyst and controlled heating conditions, the research team produced wood-derived scaffolds showing similar graphite content to petroleum-based graphite.

Through NSF's Materials World Network, this research is a collaboration among researchers at Northwestern University, the University of Seville, the Polytechnic University of Madrid and the Ioffe Institute. The catalytic technique for conversion of wood to graphite was developed at Northwestern, while researchers at Seville and Madrid focused on microscopy and mechanical properties. Ioffe Institute researchers studied the electrical and thermal conductivity of the materials.