"Nano-Pancake" Sensor Warns With Color, Rice University Study

Super-thin, color-changing films could be part of cheap sensors for food spoilage or security, say researchers. The new work led by Rice University materials scientist Ned Thomas combines polymers into a unique, self-assembled metamaterial that, when exposed to ions in a solution or in the environment, changes color depending on the ions’ ability to infiltrate the hydrophilic (water-loving) layers. Possible applications include multiband optical elements in laser-driven systems, and as part of high-contrast displays.