‘Mechanical Breathing’ in Smart Windows

Tuesday, January 21, 2020
(Funded by the National Science Foundation)

Smart windows come in many different configurations, but the most popular ones are called electrochromic devices, because they change color when a voltage is applied. Scientists at Purdue University assessed the mechanical properties at the nanoscale of the thin-film electrochromic material used in these electrochromic devices and discovered that this material can expand up to 30% in volume. This “mechanical breathing” can cause the material to wrinkle and push up against the other layers of the substrate, causing the electrochromic device to stop functioning.