Fabrication of tunable pore size of nickel membranes by electrodeposition on colloidal monolayer template

Large-area nickel patterned membranes with tunable pore size are prepared by the combination of self-assembly nanosphere lithography and electrodeposition. The morphology of the nickel membranes exhibits a honeycomb or egg-shell-roofed structure depending on the deposition time and the electrostatic-induced absorption effect. With an increase of electrodeposition time, the movement of polystyrene spheres caused by metal-filling gradually changes the contact evolution between the spheres and the substrate from facet contact to quasi-point contact, until complete lift from the substrate. Hence, the pore size can be controlled by varying the deposition time; i.e., by controlling the contact area between the polystyrene spheres and the substrate. Such membranes can be useful as templates for nanofabrication. The site and density control of one-dimensional nanostructures, depending on the distance and the size of the pore, is a critical issue in many potential applications, such as optical antennas, biosensors and bioprobes, and field emission devices.