SoylentNews

Phoenix666 [soylentnews.org] writes:

Phys.org [phys.org]:

Structural colors are a way to colorize a material without using a dye. Instead, the transparent material generates color through the regular arrangement of its molecules or other elements, as seen, for instance, in the ripples in the scales of colorful fish and butterflies, or in nanocrystals arranged at certain distances, as in the color-changing skin of chameleons.

Manos Anyfantakis and colleagues at the University of Luxembourg have identified a means to control the pitch, the distance of a full helical turn in a polymer, as a structural element on which reflection might occur and structural colors appear. Scientists can prepare liquid crystalline phases of biopolymers with pitches generating structural colors—called cholesteric phases—but these preparations depend on many parameters and need a long time to reach equilibrium.

Now, Anyfantakis and colleagues have discovered a faster and better controllable method, using liquid marbles as a platform for the controlled self-assembly of biopolymer-based structural colors. Liquid marbles are millimeter-sized droplets of liquid crystalline solutions, which are coated with nanoparticles. The coating protects the liquid from mixing with the outside fluid, but still allows for some interaction, dependent on the nature of both liquids.

The technique is expected to find application in bio-based sensors and photonics.

Original Submission