Researchers just unveiled what could be the whitest natural substance on earth. It’s composed of cellulose and inspired by the Cyphocilus beetle native to Southeast Asia. The material, which has yet to be named, is lightweight, thin, and has the ability to effectively scatter light, resulting in an exceptionally bright white color. The coating is also edible and non-toxic and could change how we use paint. The secret to the coating’s success is its insect inspiration – the beetle’s thin chitlin scales are formed in a dense light-reflecting mat that causes the beetle to appear vibrantly white.
In a new study published in Advanced Materials, scientists at the University of Cambridge and Aalto University in Finland explain how they used fine strands of cellulose, or cellulose nanofibrils, to create a scale-like membrane through a process known as mechanical defibrillation. At only a few millionths of a meter, the subsequent membrane is one of the thinnest materials ever created that is capable of appearing white. “What is cool is that with a really low amount of material, you can achieve a high intensity of reflection and whiteness,” Cambridge University researcher Dr. Silvia Vignolini told Hyperallergic. “You don’t need to have thick material to have get 100% white, 100% reflection.”
At the moment, the coating is still somewhat weak. However, researchers hope to develop a more hardy version for wider applications. “Ideally we would like to make a powder that can be readily used and applied directly as you would do with a standard pigment,” explained Vignolini. When this pigment is mixed with an organic solvent, it would then enable for the quick, one-layer application of white paint to most surfaces. The coating’s cellulose composition makes it an ideal replacement for other white products, most of which contain unsustainable materials such as titanium dioxide and zinc oxide. Importantly, the ultra-white powder will likely be quite inexpensive.
Images via Olimpia Onelli/University of Cambridge