Self-Assembly of CdSe Nanorods by Controlled Solvent Evaporation and Applied Electric Field

We report the synthesis of CdSe nanorods (NRs) having variable aspect ratios and their vertical alignment into a hexagonal arrays over a large area. NRs with a constant diameter of 6 nm and lengths, tunable to over 100 nm, were obtained by controlling the concentration of ligands in solution and injection of Se at defined time intervals. Hexagonal arrays of aligned, alkane covered CdSe nanorods within a polymer matrix were achieved by controlled solvent evaporation in the presence of an applied electric field. The nature of the solvent identity, substrate hydrophobicity, and strength of applied voltage were optimized such that close packing of nanorods was achieved over a large area. Such organized nanocomposites hold potential application in organic-inorganic bullk heterojunction photovoltaic devices.