The U.S. Army funds expansion of "flash" process

The Army Corps of Engineers will work with Prof. Tour and his collaborators at Rice University through a $5.2 million, four-year grant to expand the process that turns waste into graphene through flash Joule heating, to additional materials as well. Among the initiatives is a strategy to recover cobalt, lithium and other elements through the process developed by Tour’s group.

The grant through a Department of the Interior Cooperative Research and Development Agreement will allow the Rice-based team to extend the impact of its discovery that “flashing” food waste and other trash with a high-voltage jolt of electricity turns it into graphene. Through further experiments, the team realized the process could do much more. “We’re pushing the idea that flash Joule heating can go way beyond just graphene,” Tour said.

New strategy uses graphene quantum dots to boost catalysts

Rice University researchers, in collaboration with teams at Oak Ridge National Laboratory, University of Saskatchewan, King Abdullah University of Science and Technology and CAS, have used graphene quantum dots (GQDs) to assemble what they say may transform chemical catalysis by greatly increasing the number of transition-metal single atoms that can be placed into a carbon carrier.

General synthesis of single-atom catalysts with high metal loading using graphene quantum dots imageThe process uses functionalized graphene quantum dots to trap transition metals for higher metal loading single-atom catalysis. Illustration courtesy of the Wang Group (from Rice Uni website)

The technique uses graphene quantum dots, 3-5-nanometer particles of graphene, as anchoring supports. These facilitate high-density transition-metal single atoms with enough space between the atoms to avoid clumping.

Rice team modifies laser-induced graphene process to create micron-scale patterns in photoresist

A Rice University team has modified its laser-induced graphene technique to make high-resolution, micron-scale patterns of the conductive material for consumer electronics and other applications. Laser-induced graphene (LIG), introduced in 2014 by Rice chemist James Tour, involves burning away everything except carbon from polymers or other materials, leaving the carbon atoms to reconfigure themselves into films of characteristic hexagonal graphene. The process employs a commercial laser that “writes” graphene patterns into surfaces that to date have included wood, paper and even food.

Rice lab uses laser-induced graphene process to create micron-scale patterns in photoresist image

The new version writes fine patterns of graphene into photoresist polymers, light-sensitive materials used in photolithography and photoengraving. Baking the film increases its carbon content, and subsequent lasing solidifies the robust graphene pattern, after which unlased photoresist is washed away.

"Flash Graphene" process modified to produce graphene from rubber waste

The “flash” process, introduced by Tour and his colleagues at Rice University in 2020, has now been optimized to convert waste from rubber tires into graphene that can, in turn, be used to strengthen concrete.

Rice scientists optimized a process to turn rubber from discarded tires into turbostratic flash graphene image

The atoms reassemble into valuable turbostratic graphene, which has misaligned layers that are more soluble than graphene produced via exfoliation from graphite. That makes it easier to use in composite materials.

Rice team turns pyrolyzed ash into graphene

Researchers at Jamed Tour's lab at Rice University have developed a new process, able to convert worthless pyrolyzed plastic ash into graphene. The technique produces turbostratic graphene flakes that can be directly added to other substances like films of polyvinyl alcohol (PVA) that better resist water in packaging and cement paste and concrete, dramatically increasing their compressive strength.

Converting plastic waste pyrolysis ash into flash graphene image

Similarly to the flash graphene process the Tour lab introduced before, pyrolyzed ash turns into turbostratic graphene. That has weaker attractive interactions between the flakes, making it easier to mix them into solutions.