Recently, transmission electron microscopy (TEM) and related techniques have brought unique insights to graphene research, demonstrating remarkable flexibility in characterizations ranging from atomic ordering to charge distribution. Such TEM studies have helped advance areas including the understanding of graphene growth and the effects of defects and dopants on the mechanical and electrical properties of graphene. Electron microscopy has proved particularly useful in determining the structure of crystals and grain boundaries across six orders of magnitude—from the shapes, arrangements, and stacking sequences of grains to the atomic arrangements at grain boundaries. Meanwhile, graphene is becoming a promising two-dimensional laboratory bench for electron microscopy, for example, turning graphene into a medium for nanosculpting by transforming buckyballs into graphene and vice versa. Finally, graphene has been used as an ultrathin support membrane for TEM, enabling studies of the motion of single atoms, direct imaging of two-dimensional amorphous materials, and even formation of nano-aquaria for imaging bacteria or nanoparticles in liquid media. Rapid developments in the fields of both electron microscopy and graphene will continue to provide a rich ground for future insights.

In this article, I describe my early interest in graphene and contributions that I and my co-authors, in particular, have made to the field, along with a brief history of the experimental discovery of graphene. I then turn to new carbon materials whose experimental syntheses might be on the horizon. One example involves using graphene as a template to generate large-area ultrathin sp3-bonded carbon sheets that could also be substitutionally doped with, for example, nitrogen atoms, as one approach to making materials of interest for quantum computing. Such large-area sp3-bonded carbon sheets hold tremendous promise for use in thermal management; as a new material for electronics and photonics; and as ultrahigh-strength components in various structures including those used in aerospace, among other applications. Another example is the class of negative-curvature carbons (NCCs) that have atom-thick walls and carbon atoms trivalently bonded to other carbon atoms. Such NCCs have a nanoscale pore structure, atom-thick walls, and exceptionally high specific surface areas, and they fill three-dimensional space in ways that suggest their use as electrode materials for ultracapacitors and batteries, as adsorbents, as support material for catalysts, and for other applications.