Absorption and electrochromic modulation of near-infrared light: realized by tungsten suboxide

Abstract

In the present study, needle-like tungsten suboxide W18O49 nanocrystals were fabricated as the optical active substance to realize the aim of optical control of near-infrared light. The W18O49 nanocrystals were selected in this regard due to their unique optical performance. As revealed by the powder absorption result, the needle-like W18O49 nanocrystals show strong and wide photoabsorption in the entire near infrared region of 780-2500 nm, from which thin films with the W18O49 nanocrystal coating thus benefits and can strongly shield off almost all near infrared irradiation, whereas transmitting the majority of visible light. To make it more tunable, the W18O49 nanocrystals were finally assembled onto an ITO glass via the layer-by-layer strategy for later electrochromic investigation. The nanostructured architectures of the W18O49 nanocrystal electrochromic films exhibit high contrast, faster switching response, higher coloration efficiencies (150 cm(2) C(-1) at 650 nm and 255 cm(2) C(-1) at 1300 nm), better long-term redox switching stability (reversibility of 98% after 500 cycles) and wide electrochromic spectrum coverage of both the visible and infrared regions.

Using Intrinsic Intracrystalline Tunnels for Near‐Infrared and Visible‐Light Selective Electrochromic Modulation

“…Thus PB is selected to serve as the upper layer of the laminated electrochromic electrode in our design, in which electrochromic insertion ions are possible to penetrate throughout the structure by jumping over these A sites (or tunnels). On the other side, plasmonic W 18 O 49 nanowires are used as the lower layer of the laminated electrochromic electrode (Figure c), since these nanowires can exhibit strong plasmonic absorption in the near‐infrared region owing to the abundant oxygen vacancies and provide about three times enhancement on the near‐infrared light modulation in contrast with WO 3 films (Figure S1, Supporting Information). Here, we constructed a simple laminated double‐layer PB/W 18 O 49 electrochromic electrode for independent control over visible and NIR transmittance.…”

Recent Advances in Tungsten-Oxide-Based Materials and Their Applications

“…x O 3 , where M = Cs, Rb, K, Na, and NH 4 ) were developed by doping an element that produces a tungsten bronze structure, which in turn exhibits broadband NIR absorption properties (Kim et al, 2012;Li et al, 2016c). The aim of this review is to discuss WO 2.72 , M x WO 3 , and their hybrid-based materials to promote further scientific investigations in this field.…”

WO3Nanowires on Graphene Sheets as Negative Electrode for Supercapacitors

“…Nanostructured tungsten oxide materials have received increasing attention due to their great potential applications in gas sensors, photocatalysts, field-emission devices, and electrochromic and energy storage devices [1][2][3][4][5][6]. Nanostructured tungsten oxides as electrode materials are expected to display enhanced electrochemical performance because of their large surface area and low charge transport resistance.…”