Bio-inspired hierarchical self-assembly of nanotubes into multi-dimensional and multi-scale structures

Abstract

As inspired from nature's strategy to prepare collagen, herein we report a hierarchical solution self-assembly method to prepare multi-dimensional and multi-scale supra-structures from the building blocks of pristine titanate nanotubes (TNTs) around 10 nm. With the help of amylose, the nanotubes was continuously self-assembled into helically wrapped TNTs, highly aligned fibres, large bundles, 2D crystal facets and 3D core–shell hybrid crystals. The amyloses work as the glue molecules to drive and direct the hierarchical self-assembly process extending from microscopic to macroscopic scale. The whole self-assembly process as well as the self-assembly structures were carefully characterized by the combination methods of ¹H NMR, CD, Hr-SEM, AFM, Hr-TEM, SAED pattern and EDX measurements. A hierarchical self-assembly mechanism was also proposed.