The art of aligning one-dimensional (1D) nanostructures

One-dimensional (1D) nanostructures, including polymeric, small molecule and inorganic types, are currently being investigated in great detail for their unique mechanical, optical, electronic properties and potential implementation as devices. To integrate 1D nanostructures into device applications, it is of importance to align such nanostructures in a parallel, scalable, and highly reproducible manner independent of the specific materials. Well aligned 1D nanostructures might exhibit superior properties that are not found in their disordered counterparts, allowing promising applications in diverse fields. This critical review summarizes the recent work in the alignment of polymeric, small molecule and inorganic 1D nanostructures, in particular, the advantages and drawbacks of various aligning approaches. Discussion is focused on an advanced strategy to precisely position each 1D nanostructure by superhydrophobic pillar-structured surfaces. The research prospects and directions of this rapidly developing field are also briefly addressed (123 references).