Electrochromic devices (ECDs) represent one of the most promising energy saving and solar control technology for the market of energy-efficient building and optoelectronic devices. A continuous and intense effort is currently devoted to the development of effective solid-state ECDs and their integration in multifunctional systems, such as photoelectrochromics. Here, the fabrication of simplified all-solid-state WO based ECDs on single-substrate is reported, demonstrating how the rational design of highly interconnected WO columnar nanostructures with Nafion polymer matrix remarkably decreases the charge transport barrier at the hybrid electrolyte/electrochromic interface (EEI), thus determining an impressive improvement of overall device performances. The soft polymer substrate of the electrolyte plays a key role on the formation of WO pillar-like structures and on the increase of interfacial contact area by affecting the vacuum-deposition WO growth. Apart from providing higher transmittance in bleached state, the resulting device, entirely manufactured at room temperature by bottom-up process, exhibits lower activation voltages (0.5-3 V) and faster switching kinetics (5-10 s) compared with monolithic ECDs based on both bulk and mesoporous WO films. Furthermore, the enhanced EEI enables the scale-up on large area and flexible substrate ensuring simultaneously a wide optical contrast (?T = 70%), and high coloration efficiency.
Simplified All-Solid-State WO3 Based Electrochromic Devices on Single Substrate: Toward Large Area, Low Voltage, High Contrast, and Fast Switching Dynamics
Pugliese Marco;Maiorano Vincenzo;Gigli Giuseppe
2020
Abstract
Electrochromic devices (ECDs) represent one of the most promising energy saving and solar control technology for the market of energy-efficient building and optoelectronic devices. A continuous and intense effort is currently devoted to the development of effective solid-state ECDs and their integration in multifunctional systems, such as photoelectrochromics. Here, the fabrication of simplified all-solid-state WO based ECDs on single-substrate is reported, demonstrating how the rational design of highly interconnected WO columnar nanostructures with Nafion polymer matrix remarkably decreases the charge transport barrier at the hybrid electrolyte/electrochromic interface (EEI), thus determining an impressive improvement of overall device performances. The soft polymer substrate of the electrolyte plays a key role on the formation of WO pillar-like structures and on the increase of interfacial contact area by affecting the vacuum-deposition WO growth. Apart from providing higher transmittance in bleached state, the resulting device, entirely manufactured at room temperature by bottom-up process, exhibits lower activation voltages (0.5-3 V) and faster switching kinetics (5-10 s) compared with monolithic ECDs based on both bulk and mesoporous WO films. Furthermore, the enhanced EEI enables the scale-up on large area and flexible substrate ensuring simultaneously a wide optical contrast (?T = 70%), and high coloration efficiency.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.