Possibilities for other applications of dirty carbon


Research from Professor Grossman and others uncovers new ways to use coal, tar, and pitch to produce thin coatings with highly controllable and reproducible electrical conductivity, porosity, and other properties. Using a laser, the researchers were able make prototype devices from the inexpensive, ubiquitous materials, including a supercapacitor to store electricity, a flexible strain gauge, and a transparent heater.

Their work explores alternative ways of using carbonaceous heavy hydrocarbons, which have formed over millions of years of geological processing of decayed plant matter through heat and pressure. These materials, Grossman says, provide a rich variety of atomic configurations with different chemical and structural properties, unmatched by any synthetic, processed carbon-based nanomaterials.

To make use of these material properties, the team used a process called laser annealing to create ultrathin layers of carbonaceous materials, deposited on a substrate. They produced specific functional devices by depositing and etching patterns in layers made of different carbon-based materials. Through a combination of selecting just the right feedstock material and varying the timing and strength of laser pulses used to anneal the material, the team was able to control a range of physical, optical, electrical, magnetic, and other properties. By combining different materials, a whole range of devices could be produced at once on a single substrate.