Electrochromism

About: Electrochromism is a research topic. Over the lifetime, 13097 publications have been published within this topic receiving 294637 citations.

Electrically tunable plasmonic behavior of nanocube-polymer nanomaterials induced by a redox-active electrochromic polymer

Abstract: We present a plasmon-active hybrid nanomaterial design with electrochemical tunability of the localized surface plasmon resonances. The plasmonic-active nanostructures are composed of silver nanocube aggregates embedded into an electrochromic polymer coating on an indium tin oxide electrode with the nanocube aggregation controlled by the surface pressure. Such polymer–nanocube hybrid nanomaterials demonstrated unique tunable plasmonic behavior under an applied electrochemical potential. A significant reversible experimental peak shift of 22 nm at an electrical potential of 200 mV has been achieved in these measurements. Finite-difference time-domain (FDTD) simulations show that, under full oxidation potential, a maximal spectral shift of ca. 80 nm can be potentially achieved, which corresponds to a high sensitivity of 178 nm per refractive index unit. Furthermore, FDTD modeling suggests that the electrochemically controlled tunability of plasmonic peaks is caused by reversible changes in the refractive in...

Switchable mirrors based on nickel–magnesium films

Abstract: A new type of electrochromic mirror electrode based on reversible uptake of hydrogen in nickel magnesium alloy films is reported. Thin,magnesium-rich Ni-Mg films prepared on glass substrates by cosputtering from Ni and Mg targets are mirror-like in appearance and have low visible transmittance. Upon exposure to hydrogen gas or on reduction in alkaline electrolyte, the films take up hydrogen and become transparent. When hydrogen is removed, the mirror properties are recovered. The transition is believed to result from reversible formation of Mg2NiH4 and MgH2. A thin overlayer of palladium was found to enhance the kinetics of hydrogen insertion and extraction,and to protect the metal surface against oxidation.

Nanomaterials‐Based Electrochromics for Paper‐Quality Displays

Abstract: Electrochromic displays based on nanostructured films modified with electrochromophores are capable of becoming high quality paper-like displays due to their excellent ink-on-paper optical qualities, fast response times, and low power consuming features. The nanostractured films are composed of nanoparticles of a semiconductor, e.g., TiO 3 and other doped metal oxides. The high coloration efficiencies of these devices is due to the use of organic chromophores and the umplification of the color change due to the extremely high surface area of the nanostructured film they are bound to.

High-Contrast Electrochromism and Controllable Dissolution of Assembled Prussian Blue/Polymer Nanocomposites†

Abstract: To maintain the momentum and impact of the field, assembled materials systems must increasingly incorporate broad functionality to meet real-world applications. Here we describe nanocomposite films of specially synthesized inorganic Prussian blue (PB) nanoparticles and linear poly(ethylene imine) (LPEI) that possess the unusual functional combination of high-performance electrochromism for displays and controllable dissolution for drug delivery. Fabrication using layer-by-layer (LBL) assembly was followed by spectroelectrochemical characterization, allowing a full composition determination rarely achieved for LBL films. The electrochromic performance of thick LPEI/PB nanocomposites most relevant to applications surpassed that of inorganic PB films with competitive switching speed and superior contrast. Oxidation beyond the primary electrochromic transition removes nanoparticle ionization and can controllably dissolve the films. Because PB is non-toxic we suggest this mechanism for controlled in-vivo drug delivery. The performance and multifunctional quality of these nanocomposites promise a strong impact on flexible displays, electrochromic windows, and even biomedical devices.

Novel Metastable Hexagonal MoO3 Nanobelts: Synthesis, Photochromic, and Electrochromic Properties

Abstract: In this work, we report the crystalline structure, morphology, and optical properties of novel metastable hexagonal phase MoO3 (h-MoO3) nanobelts prepared by a simple hydrothermal route from peroxomolybdate solution with the presence of sodium nitrate as a mineralizer. During the reaction process, NaNO3 has been proposed to influence the deoxidation, condensation, and further dehydration of the water-soluble peroxomolybdate precursor for connecting the [MoO6] octahedra with vertex sharing and edge sharing arrangements on determining the generation of metastable phase. The present work comparatively investigates the photochromic and electrochromic behaviors of the resultant hexagonal h-MoO3 nanobelts and the common thermodynamically stable orthorhombic α-MoO3 nanobelts. The performances concerning photochromism on two types of MoO3 nanobelt suspensions show that the photochemical efficiency of h-MoO3 is more excellent than that of α-MoO3 under UV light irradiation based on a remarkable coloration phenomeno...