Novel exceptionally durable asymmetric double-side electrochromic device architecture

Owing to their immense potential in the fields of display boards and signage, portable/wearable electronics, adaptive camouflage, etc., the development of electrochromic materials (ECMs) and devices (ECDs) has attracted great attention from both academia and industry. However, despite the rapid progress in this area, traditional ECMs have a number of obstacles and limitations that encourage us to look for new solutions. Here we introduce a novel, non-conventional ECD architecture that includes two different electrodes separated by an opaque membrane, which is impregnated with a lithium carbonate-based electrolyte. In contrast to a traditional ECD, in which the colors of ECMs on both electrodes define the resulting color of the device, the incorporation of an opaque membrane allows for the separation of the optical properties of each electrode. Working in the bilateral mode, where the application of −2/2 V sequentially switches both sides of the device between colored and bleached states, ECD demonstrates very good stability performing 12,000 cycles. When operating in the unilateral mode, where the application of 0/2 V results in the color switch of the working electrode (WE) only, the device shows extraordinarily high stability of 100,000 cycles on iron-based side. Follow-up cycling on the osmium-based side demonstrates successful ECD performance for another 23,000 cycles. The superior long-term durability of non-conventional asymmetric double-sided ECD makes the proposed architecture promising for future practical applications.