Secondary assembly mechanism of cyclodextrin based on LiNTf 2 @β-CD system

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 β-cyclodextrin (β-CD). Nanosheet structures with regular shape were obtained in the concentrated LiNTf 2 @β-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 β-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 hydrogen-bonding network between the adjacent β-CD to regularly pack the nanotubes.