New low-cost flexible smart window material

Pulling down the shades is one way to keep the sun out of the house, but smart windows, windows of which the glass can change tint, make this unnecessary. A group of researchers at Cockrell School of Engineering at The University of Texas at Austin have invented a new flexible material that, when incorporated into windows, can control the tint of the glass electronically.

Smart windows are not new. You may remember Priva-lite that can be turned from transparent to opaque, or the newer SageGlass that can tint, reducing heat and glare, both working electronically as well. However, the new material, created by Delia Milliron, associate professor in the McKetta Department of Chemical Engineering, and her team, can be controlled by a smaller electric charge, roughly 4 volts, to lighten or darken it. Like other kinds of smart windows, the transmission of heat-producing, near-infrared radiation can be managed.

Another difference is that the new material can be attached to plastic through a low temperature process, making it a simple and low-cost alternative for more common coatings, which are applied directly to glass. Because it is flexible, the material can be sued on curved glass surfaces as well.

The material has a unique, amorphous structure, which means that the atoms do not have a long-range organisation. Thanks to the new process used by the researchers, the atoms are arranged in a linear, chain-like structure, composed of chemically condensed niobium oxide, lets ions flow in and out quite freely, making the material more energy efficient than traditional smart windows.

Courtesy photos: Cockrell School of Engineering