In the vibrant world in which we live, colors are significant for not only aesthetics and pleasure, but also for communication, signaling and security. Colors are produced through either absorption of light by molecules —pigmentary colors — or scattering of light by nanostructures — structural colors.
Structural colors enable the creation of a spectrum of non-fading colors without pigments, potentially replacing toxic metal oxides and organic pigments. However, there are challenges. Many traditional structural colors are iridescent and thus not useful for wide-angle displays. Recent examples of non-iridescent structural colors have been found to lack sufficient color saturation in the absence of absorbing materials to reduce incoherent scattering.
Core-shell nanoparticles with a shell refractive index (RI) similar to water have been used to tune the spacing between cores to achieve optimal scattering for non-iridescent colors, but only in solution. Even though both bottom-up and top-down methods have been widely used, there is a demand for a scalable process for mass production of structural colors.
In this research, scientists from The University of Akron, Northwestern University and University of Ghent demonstrate a feasible solution for producing structural colors inspired by bird feathers. Their findings have been published on Science Advances, an open access online journal established by Science. Dr. Ali Dhinojwala, above, H.A. Morton Professor of Polymer Science, is one of the principal investigators on the project.