Electrochromism

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

Tunable Properties of Mg-Doped V2O5 Thin Films for Energy Applications: Li-Ion Batteries and Electrochromics

Abstract: Vanadium pentoxide (V2O5) is doped for the first time with Mg, and the influence of Mg content on the films properties and functionality is investigated in detail, emphasis given on the electrochemical and electrochromic response. The Mg-doped V2O5 films exhibit characteristics suitable for lithium ion batteries and electrochromic window applications, the optimization of the functionality depending on the Mg content. Low Mg content (2 at. % Mg) appears to favor lithium ion battery applications, the corresponding films exhibiting high specific discharge capacity, increased diffusion coefficient, and high capacity retention. In contrast, high Mg content (15 at. % Mg) is more favorable for electrochromic windows, presenting fast switching response time, high coloration efficiency, and high visible transmittance. In both cases, the determined characteristics are superior or at least equivalent to those reported for V2O5 doped with other transition metals. The obtained results clearly indicate that tuning of t...

Reliable, High-Performance Electrochromic Supercapacitors Based on Metal-Doped Nickel Oxide.

Abstract: Herein, high-performance, reliable electrochromic supercapacitors (ECSs) are proposed based on tungsten trioxide (WO3) and nickel oxide (NiO) films. To maximize device performance and stability, the stoichiometric balance between anode and cathode materials is controlled by carefully adjusting the thickness of the anodic NiO film while fixing the thickness of WO3 to ∼660 nm. Then, a small amount (≤10 mol %) of metal (e.g., copper) is doped into the NiO film, improving the electrical conductivity and electrochemical activity. At a Cu doping level of 7 mol %, the resulting ECS exhibited the highest performance, including a high areal capacitance (∼14.9 mF/cm2), excellent coulombic efficiency (∼99%), wide operating temperature range (0-80 °C), reliable operation with high charging/discharging cyclic stability (>10,000 cycles), and good self-discharging durability. Simultaneously, the change in transmittance of the device is well synchronized with the galvanostatic charging/discharging curve by which the real-time energy storage status is visually indicated. Furthermore, the practical feasibility of the device is successfully demonstrated. These results imply that the ECS fabricated in this work is a promising potential energy storage platform and an attractive component for future electronics.

High-Contrast Solid-State Electrochromic Devices of Viologen-Bridged Polysilsesquioxane Nanoparticles Fabricated by Layer-by-Layer Assembly

Abstract: Water-soluble silsesquioxane nanoparticles (NPs) incorporating viologen groups (PXV; 1,1′-bis[3-(trimethoxysilyl)propyl]-4,4′-bipyridinium iodide) have been synthesized by sol−gel polymerization. The electrochromic properties of the bulk film fabricated by layer-by-layer (LbL) assembly have been examined, along with their incorporation into solid-state devices. The orange LbL films show high thermal stability and exhibit a maximum UV−vis absorption at 550 nm. Electrochromic switching of the NPs in liquid electrolyte as well as in the solid state was evaluated by a kinetic study via measurement of the change in transmission (% T) at the maximum contrast. Cyclic voltammograms of the PXV NP LbL films exhibit a reversible reduction at −0.6 V vs Ag/AgCl in a 0.1 M NaClO4(aq) solution, revealing good electrochromic stability, with a color change from orange to dark purple-blue at applied potentials ranging from −0.7 to −1.3 V. Cathodically coloring PXV NP solid-state devices exhibit a switching time of a few se...