Graphene Is The Strongest Material

Scientists have long suspected that graphene—chicken wire-like, two-dimensional sheets of carbon—is the strongest material ever examined. Now, that's been verified by mechanical engineering professor James Hone of Columbia University and colleagues (Science 2008, 321, 385). The task has been difficult because the slightest impurity or defect greatly affects a material's intrinsic strength. Scientists have in the past attempted to measure the strength and stiffness of nanotubes and multiple layers of graphene. Instead, the Columbia group has managed to stretch a single sheet of graphene over an array of circular holes and to use an atomic force microscope tip to indent and break through the graphene sheet into the holes. "The measured strength is over 200 times that of structural steel, and over 20 times that of advanced carbon fibers," Hone says. The authors write that the work "serves as a benchmark for structural and mechanical applications."