Template-Directed Fabrication of One-Dimensional Nanorods/Nanotubes

J. Fu, W. Knoll

in cooperation with D.-H. Kim+
(+Ewha University, Korea)
and M. Steinhart*
(*MPI for Microstructure Physics, Halle, Germany)

Fabrication of one-dimensional (1D) nanostructures has attracted considerable and increasing attention due to their potential applications in electronic, magnetic, optical, optoelectronic, and micromechanical devices. Recently, 1D nanostructures such as nanotubes, nanowires, and nanorods, have been developed using different routes. Template synthesis has been one of the most popular methods. The anodized alumina membranes with the channel diameters from tens of nanometers to hundreds of nanometers are used in this work to template the formation of polymer/block copolymer nanorods and/or nanotubes, based on melt wetting and/or solution wetting methods. These polymer/block copolymer nanorods/nanotubes are used as new templates for the fabrication of polymer/inorganic composite, in which the inorganic materials are selectively directed to some specific domains or sites within the polymer/block copolymer nanostructures.

Block copolymer nanorods have been fabricated by infiltrating the melt of, for example, PS-PMMA, into highly ordered anodized alumina templates. Using templates with different diameters and channel depths, block copolymer nanorods with different diameters and aspect ratios have been obtained (The left SEM image). Alternatively, block copolymer nanotubes can be created using solution wetting method. Undoubtedly, such nanorods/nanotubes contain internal microphase separated structure, which can be modified by properly select/control the ratio of the template diameter/wall thickness and the block copolymer period.