Colour-Changing Material Mimics Chameleon Skin

In nature, the colour-changing ability of animals, such as chameleons and cuttlefish, is attributed to chromatophores. These pigment-bearing and light-reflecting cells expand or contract (increasing or decreasing the pigment) to change body coloration and patterns across the skin.

The new material emulates this principle, but uses light-powered nano-mechanisms and microscopic drops of water in place of cells. Tiny particles of gold are coated in a polymer shell and suspended in the microdroplets of water, which are then placed in oil. When exposed to heat or light, the particles stick together – hence changing the colour of the material.

The team has developed a single layer capable of one colour change; the material appears red when the nanoparticles are spread apart, and blue when they are clustered together. However, there is potential to create a fully dynamic material using different nanoparticle materials in extra layers.

Designers and brands are starting to analyse and harness nature’s intelligence to create intuitive ecosystems, high-performance materials and sustainable solutions. Biomimicry is also an important theme in our S/S 2021 Colour & Materials direction Bio-Fantasy.

See Acoustic Panels Made with Biomaterial & Biomimicry for another example.