Researchers are taking super-thin layers of materials and stacking them into three-dimensional blocks that have properties distinct from both 2-D and conventional 3-D materials. The craze for 2-D chemistry began in 2004, when two researchers at the University of Manchester used cellophane tape to peel one-atom-thick layers of carbon from chunks of graphite, forming graphene. Graphene is identical to graphite and diamond in composition, but the thinness gives it very different properties: It is flexible, transparent, extremely strong and an exceptional electrical and thermal conductor. New York Times