Controlled growth of ZnO nanorods via self-assembled monolayer

Abstract

A simple method to achieve tailored growth of ZnO nanorods by employing self-assembled monolayer of alkanethiol molecules on a conductive substrate is introduced. Defects or pinholes in self-assembled monolayer are used to define the nucleation sites of ZnO during electrochemical deposition. The density of ZnO nanorods is tuned by the quality of self-assembled monolayer. A corresponding growth model for the growth of ZnO on self-assembled monolayer-modified substrate is proposed. The dimensions and the nucleation density of ZnO nanorods are tailored by systematically varying the quality of self-assembled monolayer and the parameters of electrochemical deposition. Furthermore, it is shown that this method also allows for laterally patterned growth of ZnO nanorods via microcontact printing of self-assembled monolayer. Electrochemical deposition of ZnO on Au surface results in dense coverage of ZnO nanorods. Self-assembled monolayers are applied on Au to tune the density of ZnO nanorods. The pinholes in self-assembled monolayer are used to define the nucleation site of ZnO.