Structural selection of graphene supramolecular assembly oriented by molecular conformation and alkyl chain.
Graphene molecules, hexafluorotribenzo[a,g,m]coronene with n-carbon alkyl chains (FTBC-Cn, n = 4, 6, 8, 12) and Janus-type "double-concave" conformation, are used to fabricate self-assembly on highly oriented pyrolytic graphite surface. The structural dependence of the self-assemblies with molecular conformation and alkyl chain is investigated by scanning tunneling microscopy and density functional theory calculation. An interesting reverse face "up-down" way is observed in FTBC-C4 assembly due to the existence of hydrogen bonds. With the increase of the alkyl chain length and consequently stronger van der Waals interaction, the molecules no longer take alternating "up-down" orientation in their self-assembly and organize into various adlayers with lamellar, hexagonal honeycomb, and pseudohoneycomb structures based on the balance between intermolecular and molecule-substrate interactions. The results demonstrate that the featured "double-concave" molecules are available block for designing graphene nanopattern. From the results of scanning tunneling spectroscopy measurement, it is found that the electronic property of the featured graphene molecules is preserved when they are adsorbed on solid surface.
Chen
Qing
Q
Institute of Chemistry and Graduate School of the Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China and Beijing National Laboratory for Molecular Sciences, Beijing 100190, China.
Chen
Ting
T
Pan
Ge-Bo
GB
Yan
Hui-Juan
HJ
Song
Wei-Guo
WG
Wan
Li-Jun
LJ
Li
Zhong-Tao
ZT
Wang
Zhao-Hui
ZH
Shang
Bo
B
Yuan
Lan-Feng
LF
Yang
Jin-Long
JL
D004563:Electrochemistry; D006108:Graphite / Q000737:chemistry*; D016252:Microscopy, Scanning Tunneling; D008958:Models, Molecular; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry; D011083:Polycyclic Compounds / Q000737:chemistry*; D013499:Surface Properties
D011083:Polycyclic Compounds; D006108:Graphite; C012256:coronene