Molecular trapping in two-dimensional chiral organic Kagomé nanoarchitectures composed of Baravelle spiral triangle enantiomers

Meiqiu Dong (1) , Xinrui Miao (2, 1) , Romain Brisse (3) , Wenli Deng (1) , Bruno Jousselme (3) , Fabien Silly (2)

1 School of Materials Science and Engineering
2 LEPO - Laboratoire d'Electronique et nanoPhotonique Organique
3 LICSEN UMR 3685 - Laboratoire Innovation en Chimie des Surfaces et NanoSciences

The supramolecular self-assembly of a push-pull dye is investigated using scanning tunneling microscopy (STM) at the liquid-solid interface. The molecule has an indandione head, a bithiophene backbone and a triphenylamine-bithiophene moiety functionalized with two carboxylic acid groups as a tail. The STM images show that the molecules adopt an "L" shape on the surface and form chiral Baravelle spiral triangular trimers at low solution concentrations. The assembly of these triangular chiral trimers on the graphite surface results in the formation of two types of chiral Kagomé nanoarchitectures. The Kagomé-α structure is composed of only one trimer enantiomer, whereas the Kagomé-β structure results from the arrangement of two trimer enantiomers in a 1:1 ratio. These Kagomé lattices are stabilized by intermolecular O-H···O hydrogen bonds between carboxylic acid groups. These observations reveal that the complex structure of the push-pull dye molecule leads to the formation of sophisticated two-dimensional chiral Kagomé nanoarchitectures. The subsequent deposition of coronene molecules leads to the disappearance of the Kagomé-β structure, whereas the Kagomé-α structure acts as the host template to trap the coronene molecules.

Domaines: Matériaux

Meiqiu Dong, Xinrui Miao, Romain Brisse, Wenli Deng, Bruno Jousselme, et al.. Molecular trapping in two-dimensional chiral organic Kagomé nanoarchitectures composed of Baravelle spiral triangle enantiomers. NPG Asia Materials, 2020, 12 (1), pp.20. ⟨10.1038/s41427-020-0201-3⟩. ⟨cea-02493808⟩