Fast Photothermal Regulation of All-in-One Electrochromic Dynamic Windows Based on Synergetic Electrodeposition of CuBi and MnO2

Electrochromic dynamic windows represent an attractive avenue for enhancing the energy-saving efficiency of buildings. However, the practical application of dynamic windows remains in its infancy due to challenges related to efficient optical modulation and cost-effective manufacturing. Herein, we report an all-in-one electrochromic dynamic window through synergetic electrodeposition of CuBi and MnO 2 , featuring a simplified three-layer configuration. The synergy of dual electrodeposition, coupled with Br − /Br 3 − redox pair, endows the CuBi//MnO 2 system with reversible color transitions between transparent and brown-black states. Benefiting from a well-balanced charge distribution, the CuBi//MnO 2 system demonstrates superior photothermal regulation in the visible-near-infrared region, including large optical modulation of 90.6% at 500 nm and 58% at 1100 nm, short response time of 16.1/12.9 s at 500 nm and 21.4/8.1 s at 1100 nm in coloration/bleaching processes. Outdoor test indicates that the assembled large-size dynamic window can lower the temperature by 5 to 10°C within a homemade house. Further simulation suggests that implementing the dynamic window can reduce annual energy consumption in buildings by up to 95.7 MJ/m 2 and decrease average CO 2 emissions by 18.8 kg/m 2 in subtropical regions of China. Our work offers a straightforward and effective strategy for developing low-cost energy-saving dynamic window technologies.