Affiliation:
1. Jiangsu Key Laboratory of Advanced Metallic Materials School of Materials Science and Engineering Southeast University Nanjing 211189 China
2. State Key Laboratory of High Performance Civil Engineering Materials Southeast University Nanjing 211189 China
3. Department of Civil and Mechanical Engineering Technical University of Denmark Kgs Lyngby 2800 Denmark
4. Molecular Science Institute School of Chemistry University of the Witwatersrand Private Bag 3, Wits 2050 Johannesburg 2000 South Africa
Abstract
AbstractThe integration of electrochromic devices and energy storage systems in wearable electronics is highly desirable yet challenging, because self‐powered electrochromic devices often require an open system design for continuous replenishment of the strong oxidants to enable the coloring/bleaching processes. A self‐powered electrochromic device has been developed with a close configuration by integrating a Zn/MnO2 ionic battery into the Prussian blue (PB)‐based electrochromic system. Zn and MnO2 electrodes, as dual shared electrodes, the former one can reduce the PB electrode to the Prussian white (PW) electrode and serves as the anode in the battery; the latter electrode can oxidize the PW electrode to its initial state and acts as the cathode in the battery. The bleaching/coloring processes are driven by the gradient potential between Zn/PB and PW/MnO2 electrodes. The as‐prepared Zn||PB||MnO2 system demonstrates superior electrochromic performance, including excellent optical contrast (80.6%), fast self‐bleaching/coloring speed (2.0/3.2 s for bleaching/coloring), and long‐term self‐powered electrochromic cycles. An air‐working Zn||PB||MnO2 device is also developed with a 70.3% optical contrast, fast switching speed (2.2/4.8 s for bleaching/coloring), and over 80 self‐bleaching/coloring cycles. Furthermore, the closed nature enables the fabrication of various flexible electrochromic devices, exhibiting great potentials for the next‐generation wearable electrochromic devices.
Funder
National Key Research and Development Program of China
Fundamental Research Funds for the Central Universities
Aeronautical Science Foundation of China
Natural Science Foundation of Jiangsu Province
National Natural Science Foundation of China