Solar cells, fiber-optic cables, paints and cosmetics—they're all pretty good, but scientists know a way to make them even better: use biophotonic crystals.
These little structured crystals would, for example, improve the efficiency of data transfer in fiber-optics. They affect the motion of light particles (photons) in a similar way to how regular lattice structures channel the motion of electrons. Biophotonic crystals could be used to direct photons through fiber-optic cables, or even to create beautiful colors in paint.
The trouble is, it's really tricky to get biophotonic crystals to order themselves precisely and neatly. But it looks like nature has the answer, as insects have been arranging biophotonic crystals on their little bodies for years and years.
The scientists used high-intensity X-rays at the Argonne National Laboratory to image a wide range of insects that have these nanostructures—from the beautiful butterfly to the terrifying tarantula, the buzzing bee to the wiggly weevil. The high-intensity X-rays create detailed images that allowed the researchers to investigate the color-producing nanostructures on the hair-like structures that cover the insects.
“These biophotonic nanostructures have the same shapes commonly seen in blends of large, synthetic, Lego-like molecules called block copolymers, developed by chemists,” said lead author Vinod Saranathan, faculty member at Yale-NUS College.
It turns out that the insects had figured out how to order the crystals by making them a little bit bigger than the scientists were trying to work with. By making the crystals an order of magnitude bigger, the insects are somehow able to order them in periodic arrangement. The larger size is also responsible for the beautiful, saturated colors that the insects model.
“Arthropods such as butterflies and beetles, which have evolved over millions of years of selection, appear to routinely make these photonic nanostructures using self-assembly and at the desired optical scale just like in modern engineering approaches,” said Richard Prum, senior author of the paper.