Cost-Effective, Flexible, and Colorful Dynamic Displays: Removing Underlying Conducting Layers from Polymer-Based Electrochromic Devices.

Electrochromic (EC) materials and devices provide a user-controlled, dynamic way of displaying information using low power, making them interesting for a range of applications in numerous markets, including logistics, retail, consumer goods, and health care. To optimize the cost while simplifying the production, expanding the color space, and enhancing the contrast and vibrancy of EC displays aimed for cost-sensitive products, we sought to reduce the number of layers as well as remove the underlying conducting layer that accounts for a substantial fraction of the cost of a printed label. Here, we show how conjugated electrochromic polymers, which are inherently semiconducting, can be used to accomplish this goal and afford printable EC displays with a flexible form factor.