Japanese scientists from Kobe University (KobeU) have developed a dye nanocoating consisting of microscopic silicon spheres. They create shadows by reflecting light of a certain length. The research was published in the official gazette Web site Kobe U.
Our eyes see certain colors due to the reflection of light from objects of different wavelengths. In the case of conventional pigments, the hue depends on which colors in the composition of white light are absorbed by the illuminated surface and which are not. Over time, this interaction leads to molecular degradation and fading.
Another coloring effect is called structure color. It occurs when light is reflected from parallel nanostructures located at a desired distance from each other. As a result, only light of a certain wavelength remains, while other shadows fade out. It is possible to observe this phenomenon on the wings of butterflies or the feathers of peacocks. Structural colors do not fade, but their hue depends on the viewing angle, making the material iridescent.
Materials scientists at Kobe University created colloidal suspensions of spherical and crystalline silicon nanoparticles. These fragments scatter light into bright colors through what is called the “Mie resonance”, which allows the development of structured color inks.
In the Mie resonance, spherical particles whose size is comparable to the wavelength of light reflect waves of a particular wavelength particularly strongly. This essentially means that the color from the suspension can be easily controlled by varying the particle size.
This effect made it possible to cover objects with a structural color that did not change depending on the viewing angle.
“A single layer of sparsely dispersed silicon nanoparticles, just 100-200 nanometers thick, exhibits vibrant colors but weighs less than half a gram per square meter. This makes our silicon nanospheres one of the lightest-colored coatings in the world,” explained one of the authors of the development of the material Engineer Hiroshi Sugimoto.
According to scientists, paint nanocoating may have many uses. For example, silicone coating could be used to lighten an aircraft by several hundred kilograms, as it would weigh only 10% of the weight of standard aircraft paint.
Previous scientists promise Creating a nano-coating that will heal scratches and other damage for devices by 2028.