Gate-controlled electron transport in coronenes as a bottom-up approach towards graphene transistors

Abstract

Graphene is considered to be a large aromatic molecule, the limiting case of the family of polycyclic aromatic hydrocarbons. This fascinating two-dimensional material has many potential applications, including fi eld effect transistors (FETs). However, the graphene sheets in these devices have irregular shapes and variable sizes, and contain various impurities and defects, which are undesirable for applications. Moreover, the bandgap of graphene is zero and, consequently, the on / off ratios of graphene FETs are small, making it diffi cult to build logic circuits. To overcome these diffi culties, we report here a bottom-up attempt to fabricate nanoscale graphene FETs. We synthesize structurally well-defi ned coronene molecules (consisting of 13 benzene rings) terminated with linker groups, bridge each molecule to source and drain electrodes through the linkers, measure conductance and demonstrate the FET behaviour of the molecule.

Towards graphyne molecular electronics

“…This value represents the largest reported SMC of any amine-anchored molecule of similar length, such as a porphyrin or a highly conjugated oligophenylene-ethynylene (Supplementary Table 1). In particular, the SMC of the a-graphyne molecular fragment A studied here is much larger (106 nS through 1.94 nm) than that of the shorter, and therefore in principle more conductive, graphene molecular fragment hexabenzocoronene (HBC) measured with the same technique (14 nS through 1.4 nm) 29 . The conductance of carbo-benzene can also be compared with another class of molecules previously studied by our group 27 .…”

Theoretical study of stability and charge-transport properties of coronene molecule and some of its halogenated derivatives: A path to ambipolar organic-based materials?

“…12 Another strategy currently pursued in hydrocarbons as 2,6 :2 ,6 -terazulene revealed an asymmetrical distribution of the frontier molecular orbitals leading to (in this case) a preferred n-type behavior. 13 In an attempt to disclosure existing relationships between specific substitution patterns and corresponding ambipolar (if any) behavior, we have chosen to start from a 2D-shaped molecule such as coronene (hexabenzobenzene), see Figure 1, which has been thoroughly studied in last years, [14][15][16] and systematically study the influence of full and partial halogenation (fluorination and chlorination) in the bulk of properties related with charge transfer. We remark that molecular order at the nanoscale is revealed of utmost importance.…”

Molecular Tips for Scanning Tunneling Microscopy: Intermolecular Electron Tunneling for Single-molecule Recognition and Electronics

“…In molecular electronics, individual molecules or a small group of molecules are utilized as electronic components, such as wires, 6,7 diodes, [8][9][10] switches, 11,12 and transistors, 13,14 to perform certain electronic functions. 15 Therefore, the most fundamental question in this field is what is the electronic conductance of a junction composed of a single (or a few) molecule(s).…”

“…These studies have been motivated by increasing interest in molecular electronics, which utilizes an individual molecule or a small group of molecules as an electronic component to perform certain functions. A large number of molecules with unique electronic functions, e.g., wires, 6,7 diodes, [8][9][10] switches, 11,12 and transistors, 13,14 have been reported. 15 We have developed molecular tips for STM.…”