简介: |
Abstract：
June cover article in C&EN offers a broad retrospect of carbon nanotube research within a framework of Gartner’s hype peak, tacitly inviting the readers to similarly gauge the peak phases for graphene or for 2D materials “beyond” it. Accordingly, to give a modest account of work in my lab, I focus on three recent advances in these areas. First one concerns the nanotubes, where it took two decades to derive a kinetic formula R ~ sinx (growth rate R, helical angle x). Further analysis of the subtle balance between the kinetic and thermodynamic views reveals sharply peaked abundance distribution A ~ xexp(-x). This explains the puzzling (n, n-1) types observed in many experiments. In the second example, a combination of DFT and Monte Carlo models explains the low symmetry shapes of graphene on substrates. In equilibrium, edge energy variation dE manifests in slightly distorted hexagons. In growth, it enters as ~exp(-dE/kBT), amplifying the symmetry breaking to triangle, ribbon, rhomb. Third example concerns 2D materials of more complex chemistry, h-BN and MX2 among them, how their defects, dislocations and grain boundaries, predicted from the first principles, find remarkable experimental confirmations and lead to new tantalizing predictions.
Professor Boris I. Yakobson is Karl F. Hasselmann Chair Professor of Engineering, Professor of Materials Science and Nano-Engineering, and Chemistry, Rice University, Houston, Texas, USA.
He is an expert in theory and computational modeling of nanostructures, including of their synthesis, mechanics, defects and relaxation, and transport and electronics. Until now he has published more than 250 papers and seven patents.
Yakobson has mentored a number of PhD students and postdoctoral associates, serves on the editorial boards of several journals and on steering committees. |
