Graphene Staying Strong: Although exfoliated graphene can be extremely strong, it is produced on too small a scale for materials application. Graphene can be produced on a more practical scale by chemical vapor deposition, but the presence of grain boundaries between crystallites apparently weakens the material. Lee et al. (p. 1073 ) show that postprocessing steps during the removal of the graphene sheets can oxidize the grain boundaries and weaken them. If these steps are avoided, the material is comparable in strength to exfoliated graphene.