Secondary assembly mechanism of cyclodextrin based on LiNTf2@β-CD system

Abstract

Cyclodextrin-based nanotubes have been widely investigated and their secondary assembly (SA) behavior was found in our previous works. Here we report the self-assembly behavior between lithium bis(trifluoromethylsulfonyl)imide (LiNTf 2 ) and b-cyclodextrin (b-CD). Nanosheet structures with regular shape were obtained in the concentrated LiNTf 2 @b-CD solution. This phenomenon can be explained in terms of the SA mechanism of CD induced by the inorganic guest LiNTf 2 . LiNTf 2 and b-CD firstly forms nanotubes, and the nanotubes further stack with each other to form nanosheets by SA. We confirm that the hydrogen-bonding interaction contributes a lot to the formation of the nanotubes and their SA, and Li ? shows a special effect in the SA by inducing hydrogenbonding network between the adjacent b-CD to regularly pack the nanotubes.

2-O-Methylated β-Cyclodextrin as an Effective Building Block to Construct Supramolecular Assemblies with Various Morphologies and Molecular Arrangements

“…In addition, some interactions between the 2-Me-β-CD molecules and the HOPG surface, such as van der Waals forces and/or CH−π interactions, could trigger the assembly mode change. A similar phenomenon was reported by Yasuda et al , in which α-CD molecules formed a channel assembly through two-dimensional crystal growth on HOPG and MoS 2 substrates; however, the change in the assembly mode observed in this study is an unprecedented type of assembly transition for β-CD without guest inclusion, as native β-CD typically transforms from a cage-type to a head-to-head channel-type assembly through the inclusion of appropriate guest molecules. − …”