Template-induced directional growth of ZnO nanomeshes by colloidal crystals

The formation of materials with controllable morphologies is of great significance both in science and technology. In this paper, a new method for controlling the morphology of materials is introduced: the chemical effects and the geometric restriction of the template are both utilized for determining the shape of growing materials. We report a thermodynamic study on the formation process of novel two-dimensional zinc oxide (ZnO) nanosheets with periodically porous structures (nanomeshes) grown in a template of colloidal crystals by an electrochemical-deposition method. The geometry restriction of the colloidal crystal template and the template-induced anisotropic environments are both introduced in the electrodeposition. ZnO nanomeshes along the {111}, {110}, and {100} crystalline planes of the colloidal crystals and nanomeshes with curved shapes are synthesized through the modification of the depositing conditions and template parameters. A model on the basis of thermodynamic stability is proposed to describe the relationship between the directional growth of nanomeshes and their influencing factors including surface energy, deposition time, and microsphere diameters.