Advanced Dual‐Band Smart Windows: Inorganic All‐Solid‐State Electrochromic Devices for Selective Visible and Near‐Infrared Modulation

• Published in: Advanced functional materials
• Main Authors: Chen, Mingjun, Deng, Jianbo, Zhang, Hulin, Zhang, Xiang, Yan, Dukang, Yao, Gengxin, Hu, Liping, Sun, Shuokun, Zhao, Jiupeng, Li, Yao
• Format: Journal Article
• Language: English
• Published: 30.09.2024
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202413659

Abstract Dual‐band electrochromic smart windows (DESWs), capable of actively and selectively modulate visible (VIS) light and near‐infrared (NIR) heat, have emerged as a practical technology for enhancing user comfort and reducing building energy consumption. However, the design and development of DESWs remain a significant challenge due to the difficulty in obtaining suitable materials and high‐durability electrolytes. Here, the first all‐solid‐state DESW based on an orthorhombic oxygen‐deficient tungsten oxide (o‐WO 3‐ x ) film is presented. Benefiting from the synergistic effects of the efficient oxygen‐vacancy‐enhanced charge transfer process and the secure transfer pathway enabled by the orthorhombic crystal structure, the o‐WO 3‐ x film showcases remarkable dual‐band electrochromic properties, including selective modulation of VIS light and NIR heat, large optical modulation (89.1%), rapid response time ( t b / t c = 6.8/17.9 s), high coloration efficiency (155.92 cm 2 C −1 ), and ultrastable cyclic performance (8000 cycles) even in acidic aqueous electrolyte. Furthermore, the all‐solid‐state DESWs incorporating o‐WO 3‐ x deliver a significant and stable dual‐band electrochromic response with excellent thermal regulation and energy‐saving capabilities. These findings underscore the considerable potential of o‐WO 3‐ x films and their all‐solid‐state smart windows in decreasing building energy consumption.