Various Coating Methodologies of WO3 According to the Purpose for Electrochromic Devices

Abstract

Solution-processable electrochromic (EC) materials have been investigated widely for various applications, such as smart windows, reflective displays, and sensors. Among them, tungsten trioxide (WO3) is an attractive material because it can form a film via a solution process and relative low temperature treatment, which is suitable for a range of substrates. This paper introduces the slot-die and electrostatic force-assisted dispensing (EFAD) printing for solution-processable methods of WO3 film fabrication. The resulting films were compared with WO3 films prepared by spin coating. Both films exhibited a similar morphology and crystalline structure. Furthermore, three different processed WO3 film-based electrochromic devices (ECDs) were prepared and exhibited similar device behaviors. In addition, large area (100 cm2) and patterned ECDs were fabricated using slot-die and EFAD printing. Consequently, slot-die and EFAD printing can be used to commercialize WO3 based-ECDs applications, such as smart windows and reflective displays.

Heat-Insulating Black Electrochromic Device Enabled by Reversible Nickel–Copper Electrodeposition

“…The ECD can be switched from the transparent state (visible light transmittance: 0.566) to the colored state (visible light transmittance: 0.003) by electrodeposition at −3.0 V within 1 min. The black-colored ECD ( L * = 2.43, a * = 2.19, and b * = 3.08) can achieve superior color neutrality with a C * value of 3.78, which is comparable to the state-of-the-art dynamic window with a C * value of approximately 3 at the black state. , Additionally, in comparison to the dark state of the ECD manufactured with the WO 3 -coated working electrode, which always exhibits a large value of L * (>25) and C * (>20) due to its blue color, our black-colored ECD shows a more visually flawless black hue. − …”

Photonic Drying/Annealing: Effect of Oven/Visible Light/Infrared Light/Flash-Lamp Drying/Annealing on WO3 for Electrochromic Smart Windows

“…The coloration efficiencies (η) for the prepared WO 3 ECDs dried by oven/IR light/visible light/flash-lamp were 65.4, 58.2, 77.3, and 67.8 cm 2 /C, respectively, and the obtained results are compared with the recent literature (Table ). ,− Furthermore, the high coloration efficiency (η) clearly suggests the low power consumption to get a high color contrast/bleaching state as optical modulation dynamics. The crystalline nature of WO 3 dried under light shows a number of pores and sharpened edges, which facilitates a higher number of paths for electron movement, in turn resulting in increased adsorption of ions in the electrolyte; due to attraction forces of electrons, the overall rate of diffusion ions is increased.…”

Supported-Metal Oxide Nanoparticles-Potential Photocatalysts

“…Recently, the researchers have proposed many strategies for the fabrication of WO 3 thin film [88], such as sputtering deposition [89][90][91][92], aerosol-assisted chemical vapor deposition [93,94], sol-gel spin-coating [95,96], hydrothermal-assisted growth [97,98], and surfactant-assisted spray pyrolysis [99,100]. Many works focused on the photocatalytic efficiency of WO 3 , especially the studying of WO 3 thin film as a photocatalyst in the visible region [84,101].…”