Fast and versatile deposition of aligned semiconductor nanorods by dip-coating on a substrate with interdigitated electrodes

Abstract

Semiconductor nanorods mainly absorb and emit light with the electric field along the axis of the rods, it is therefore important to align the nanorods along a preferred direction. The homogeneous deposition of aligned nanorods on large substrates is interesting for large size applications such as solar cells and OLEDs. In this work, we present a fast and versatile method for the homogeneous deposition and alignment of nanorods from a colloidal suspension. The method is based on a low-cost dip-coating procedure during which an alternating electric field is applied. The accumulation, orientation, and polarized fluorescence of the nanorods is verified by AFM and polarized fluorescence microscopy. An alignment with order parameter of 0.67 has been obtained with this method.