Electrochromic Textiles and Devices

The Sotzing group is committed to the development of new electrochromic materials; polymers which switch their colored states based upon the application of a voltage difference. Small operating voltages (+/- 1.5 V) and low power-consumption (1.55 mW / cm2) are common characteristics of electrochromic devices or “ECDs.” Electrodeposition is a costly technique, however, and our group has developed the Precursor Polymer method. We create precursor polymers, which are soluble and processable, and then convert them to their working, electrochromic form after they have been patterned as desired. This offers tremendous versatility for applications such as smart-windows and advanced textiles. These movies tell the story very well.

ECD Movie (20.5 MB): Traditional, electrodeposited ECD (using glass, plastic, and ITO) going from neutral (deep, absorptive purple-blue) to oxidized (light, transmissive sky-blue) and back.

Precursor Movie (18.3 MB): A plastic/ITO window-type device assembled with the precursor polymer. This device converts the precursor (yellow) to the oxidized state of the polymer (blue) and back to the neutral state (red). It continues to switch blue to red.

Electrochromic Textile Movie (17.6 MB): A movie of a simple electrochromic fabric device switching between colored states.

Sunglasses Movie (64.6 MB): Using the same precursor technology as above, this device was assembled and switched with a simple, small lithium watch battery. The switch is faster than any photochromic lens technology, and is controllable and reversible. Many other colors could be achieved using this technology, as well.