Electric-field-assisted assembly of perpendicularly oriented nanorod superlattices.

We observe the assembly of CdS nanorod superlattices by the combination of a DC electric field and solvent evaporation. In each electric-field (1 V/microm) assisted assembly, CdS nanorods (5 nm x 30 nm) suspended initially in toluene were observed to align perpendicular to the substrate. Azimuthal alignment along the nanorod crystal faces and the presence of stacking faults indicate that both 2D and 3D assemblies were formed by a process of controlled super crystal growth.