Emerging Zn Anode‐Based Electrochromic Devices

Abstract

The development of electrochromic materials has opened the door to the development of numerous devices including smart windows, color displays, optical filters, wearable camouflages, among others. Although the current electrochromic devices do not consume energy while maintaining their colored or colorless states, their bistable operation requires external electrical energy to be consumed during switching. To reduce the energy consumption of an electrochromic device, an emerging Zn anode‐based electrochromic device concept was recently introduced to partially retrieve the consumed electrical energy. In this Review, key technological developments and scientific challenges are presented for a broad range of Zn anode‐based electrochromic device configurations with emphasis on the inherent distinctions between the Zn anode‐based and conventional electrochromic devices. Specifically, a comprehensive comparison of the two classes of electrochromic devices in the high‐performance device design is provided. For the electrochromic layer, the methods for obtaining high‐quality electrochromic materials and thin films are reviewed. For the electrolytes, the effect of the dual ion system on the electrochromic performance is discussed. Also, some critical but unresolved issues in the device design and fabrication are discussed. The perspectives and outlook at the end of this Review provide recommendations to improve performance for future electrochromic studies.

Self-Driven Electrochromic Window System Cu/WOx-Al3+/GR with Dynamic Optical Modulation and Static Graph Display Functions

“…Recently, a new class of electrochromic windows using active metal anodes (Al, Mg, Zn, Fe) was reported by some laboratories. − In these window prototypes, the opaque anode was concealed in the window-frame parts, and the electrochromic cathode (inorganic metal oxide and/or organic conducting polymer) was immersed in an aqueous mixed electron/ion conducting electrolyte (as illustrated in Figure S1b). Benefiting from the design of the asymmetric structure, the active metal-based electrochromic windows can implement multiple functions of visual energy storage, optical/thermal modulation, and stable multicolored display. , Compared with traditional symmetric-type configurations, the active metal-based electrochromic windows have the following two main technical advantages.…”

Inkjet-Printed Dual-Mode Electrochromic and Electroluminescent Displays Incorporating Ecofriendly Materials

“…The coloring switching times of both device types are below 1 s. Thus, we observed no drawbacks in the performance of the ECD when using the ecofriendly electrolyte compared to the fluorinated reference. More advanced EC device architectures include ion storage layers or optimized electrodes . However, we opted for a simplified architecture for the DMDs as the ECL devices are based on ITO electrodes…”

“…More advanced EC device architectures include ion storage layers or optimized electrodes. 53 However, we opted for a simplified architecture for the DMDs as the ECL devices are based on ITO electrodes…”

Recent Advances in Inorganic Electrochromic Materials from Synthesis to Applications: Critical Review on Functional Chemistry and Structure Engineering

“…Newly adopted active metals (e. g., Al, Zn) offer significant advantages, such as having high theoretical specific capacity, low cost, and being highly abundant. [14] However, Type I EC system was still the most widely used one, where both EC materials must have colorless bleached and colored states in the EC system, and the materials as the primary electrochromic species usually have the highest coloration efficiency. [9] Consequently, the system switches from the bleached state to the colored state and maintains its color upon completion of electrochemical coloration.…”