Electrochromic-Tuned Plasmonics for Photothermal Sterile Window

Abstract

Electrochromic materials are widely used in smart windows. An ideal future electrochromic window would be able to control visible light transmission, tune building's heat conversion of near-infrared (NIR) solar radiation, and reduce attacks by microorganisms. To date, most of the reports have primarily focused on visible-light transmission modulation using electrochromic materials. Herein, we report the fabrication of an electrochromic-photothermal film by integrating electrochromic WO with plasmonic Au nanostructures and demonstrate its adjustability during optical transmission and photothermal conversion of visible and NIR lights. The localized surface plasmon resonance (LSPR) of Au nanostructures and the broadband nonradiative plasmon decay are proposed to be tunable using both the electric field and the WO substrate. Further enhanced photothermal conversion is achieved in colored state, which is attributed to coupling of traditional visible-band optical switching with NIR-LSPR extinction. The resulted electrochromic-photothermal film can also effectively reduce the numbers of attacking microorganisms, thus promising for use as a sterile smart window for advanced applications.

Flexible and Transparent Electrochromic Displays with Simultaneously Implementable Subpixelated Ion Gel‐Based Viologens by Multiple Patterning

“…Recently, electrochemical devices have attracted considerable attention for their ability to satisfy such demands. Furthermore, compared to conventional devices, electrochemical devices have many additional advantages, such as low‐voltage operation, simple structure, and use of various electrodes independent of work function . The representative device based on electrochemistry is an electrochromic (EC) device.…”

“…The representative device based on electrochemistry is an electrochromic (EC) device. EC devices that exhibit reversible color changes by modification of optical properties based on oxidation states have been developed for diverse applications including smart windows, large‐area signage, mirrors, light‐shutters, military equipment camouflage, and reflective displays . In general, EC devices are classified into three forms: type I, type II, and type III, according to the solubility of the redox species in the electrolyte.…”

“…One of the widely used EC materials is the viologen (1,1′‐substitued‐4,4′‐bypyridium salt) and it has attracted attention as a stable redox species with high stability of the radical cations, excellent electron‐accepting capability, and good tunability of the substituents . The viologens exhibit various colors depending on the forms and chain lengths of the substituents.…”

Active control of plasmonic colors: emerging display technologies

“…22 Similar work on modulating reflected colors using nanowells and polypyrrole was recently presented by Atighilorestani et al 86 A possible future inorganic alternative to conductive polymers for switching the plasmonic colors is electrochromic metal oxides. 87…”

Electrochromic Device Composed of a Di-Urethanesil Electrolyte Incorporating Lithium Triflate and 1-Butyl-3-Methylimidazolium Chloride

“…Plasmonics was used to fabricate first a dual-band smart windows with selective and independent control of visible and NIR radiation, and later three-mode smart windows displaying bright mode (visible and NIR admitted), cool mode (visible admitted and NIR blocked), and dark mode (visible and NIR blocked) (Llordes et al, 2013;Kim et al, 2015). A sterile smart window composed of plasmonic gold nanostructures combined with WO 3 was able to control optical transmission and photothermal conversion of visible and NIR lights (Xu et al, 2018). Completely different approaches were adopted more recently.…”