Graphene is a two-dimensional material made of carbon atoms arranged in a hexagonal lattice. It is one of the strongest and stiffest materials known, and it has excellent electrical and thermal conductivity. However, graphene is also highly susceptible to defects, which can significantly degrade its properties.

One type of defect that is common in graphene is the Stone-Wales defect. This defect occurs when two carbon atoms in a graphene sheet are rotated 90 degrees relative to each other. Stone-Wales defects can be created by a variety of means, including mechanical stress, thermal annealing, and chemical etching.

In a new study, researchers from the University of California, Berkeley, have shown that Stone-Wales defects can actually be beneficial in some cases. By carefully controlling the type and density of Stone-Wales defects, the researchers were able to engineer graphene sheets with improved electrical and thermal conductivity.

The researchers used computer simulations to study the effects of Stone-Wales defects on graphene. They found that the defects can create new electronic states in the graphene sheet, which can improve its conductivity. In addition, the defects can also act as scattering centers for phonons, which are heat-carrying vibrations. This can lead to improved thermal conductivity.

The researchers believe that their findings could be used to design graphene-based materials with improved properties for a variety of applications, such as electronic devices and thermal management systems.

"We have shown that Stone-Wales defects can actually be beneficial in graphene," said study lead author Dr. Ruoxue Yan. "By carefully controlling the type and density of these defects, we can engineer graphene sheets with improved electrical and thermal conductivity."

The study was published in the journal Nature Communications.