Gas Molecules on Graphene
Graphene-the arrangement of carbon atoms on a bipartite planar hexagonal lattice (see Figure 24.1)—has been the starting point in all calculations on graphite, CNTs, and fullerenes since the late 1940s (Wallace 1947), but its experimental realization has been postponed till 2004 (Novoselov et al. 2004) when a technique called micromechanical cleavage was employed to obtain the šrst graphene crystals. ™e observation of a peculiar electronic spectrum (Novoselov et al. 2005, Zhang et al. 2005), high electron mobility (Novoselov et al. 2004, Morozov et al. 2008), and the possibility of electronic as well as gas-sensing applications (Schedin et al. 2007) initiated enormous interest in this šeld (for reviews, see Castro Neto et al. 2009, Geim and Novoselov 2007, Katsnelson and Novoselov 2007).