Nanotechs Control Liquid Color with Magnets

University of California, Riverside nanotechnologists have succeeded in controlling the color of very small particles of iron oxide suspended in water simply by applying an external magnetic field to the solution. The discovery has potential to greatly improve the quality and size of electronic display screens and to enable the manufacture of products such as erasable and rewritable electronic paper and ink that can change color electromagnetically.

Yadong Yin, an assistant professor of chemistry who led the research said the new technology can be used to make an inexpensive color display by forming millions of small pixels using the photonic crystals. "A different color for each pixel can be assigned using a magnetic field," he said. "The advantage is that you need just one material — for example, photonic crystals like iron oxide — for all the pixels. Moreover, you don’t need to generate light in each pixel. You would be using reflected light to create the images — a form of recycling."

Nanotech Now