Solvent spray method for simple fabrication of surface nanostructures of molecular thin films

In this work, zinc phthalocyanine (ZnPc) nanorods with various aspect ratios were effectively fabricated by spraying acetone/water mixed solvents onto the surface of ZnPc thin films. The lengths of the nanorods formed varied with the composition of the solvents used. The electronic absorption band of the film was broadened by the treatment, but it was almost completely recovered by post-annealing the film at 200 degrees C. This spray method is very simple compared to conventional surface nanostructuring technologies such as nanoimprinting and applicable to most organic films since the amount and composition of the solvents used are easily controllable.