"In that case, perhaps we need to replicate the actual structure," says Lakhtakia. "One insect has an iridescent shell that does not change colors as many shiny ones do. No one has made this type of material artificially because we do not know the mechanism by which it retains its color, but making a template from the actual insect would replicate the fine structure of the surface."
Many things in the natural world are colored not by pigment, but by surface structure. The way light interacts with the surface creates the color, rather than any tint or chemical. Reproducing the surface reproduces the color. Surface properties include not just visible light characteristics, but also infra red, thermal, stickiness and other characteristics.
Martn-Palma, Pantano and Lakhtakia's work creates either a replica template or a mold depending on what they coat. The replica of a template can be used to create a mold in a harder, less damageable material to make many copies. Molds can be combined and multiplied to create the desired surfaces.
The researchers initially looked at surfaces with optical properties because they are easy to see and identify. The structural black of some butterflies invites investigation of thermal properties as well. Creating surfaces that have micro or nanoscale patterns on solar cells, heat exchangers, reflectors and lenses can produce devices that work more efficiently.
"The whole world of biomimetics and bioinspiration is just beginning to emerge," says Martn-Palma. "Butterfly wings come in a large variety of surface structures. Eventually we may be able to take these biological structures and modify
|Contact: A'ndrea Elyse Messer|