2024-03-08

Preparation of WO3-based flexible electrochromicfabrics and their near

infrared shieldingapplication†

   In this work, tungsten trioxide (WO3) films are prepared on carbon cloth using a one-step hydrothermalmethod. All results reveal that a variety of WO3 nanostructures including nanoparticles, nanoplates, 3Dnanorod flowers, nanorods, and nanobundles can be obtained by modulating the pH of the precursorsolution. The electrochromic performance of different nanostructure films has been investigated. Thehexagonal WO3-1.6 presents the highest electrochromic properties with a reflection contrast

(DR) of38.83% at 410 nm, and a coloring and bleaching time of 2.59 and 5.29 s at 800 nm, respectively. Theelectrochromic fabric can realize the color change from light blue to blue purple to blue black in thevoltage range of 1.2 to 1.5 V. There is no significant degradation of the electrochromic properties after100 coloring/bleaching cycles, making it attractive for practical applications. In addition, electrochromicfabrics in the field of near infrared thermal shielding have been studied. When used as a windowshielding, the difference of temperature rise (6.2 1C) in the container of the WO3-1.6 colored state afterexposure

to light is significantly lower than that of carbon cloth (11.3 1C) or cotton cloth (11.8 1C). In thecase of contact shielding, the temperature difference of the cotton cloth shielded by the bleachedsample before and after exposure to the same light is up to 2.6 1C. These results confirm that the WO3electrochromic fabric has good electrochromic and thermal shielding properties, which provides thepossibility for the wearable functional applications of flexible electrochromic fabrics.

Li M, Jiang W, Lin Y, et al. Preparation of WO 3-based flexible electrochromic fabrics and their near infrared shielding application[J].

Journal of Materials Chemistry C, 2024, 12(15): 5420-5430.