Sputtering Flexible VO Films for Effective Thermal Modulation.

Flexible vanadium dioxide (VO) thermochromic films show great potential for large-scale fabrication and possess broader applications compared with VO coatings on rigid substrates. However, the fabrication of flexible VO films remains a challenge so far, leading to the scarcity of research on flexible VO films for smart windows. With the aim to obtain a flexible VO-based films with excellent optical properties and a long service life, we designed and successfully fabricated a flexible ITO/VO/ITO (IVI) film on the colorless transparent polyimide substrate, which could be directly attached to glasses for indoor temperature modulation.

Tuning Phase Transition and Thermochromic Properties of Vanadium Dioxide Thin Films via Cobalt Doping.

Vanadium dioxide (VO) featuring a distinct thermally triggered phase transition is regarded as the most attractive thermochromic material for smart window applications. However, the high transition temperature (∼67 °C) and moderate luminous transmittance (<50%) of the pristine VO circumvent room temperature applications. In this work, epitaxial cobalt-doped VO thin films were fabricated to tailor the electric and optical properties on a -plane sapphire substrate.

Morphology-controlled WO homojunction: hydrothermal synthesis, adsorption properties, and visible-light-driven photocatalytic and chromic properties.

In this paper, a facile one-step hydrothermal method for the synthesis of crystalline-amorphous WO core-shell nanopowders (nanoparticles, nanorods, and nanowires) is reported. The core-shell structure, the size and the morphology of the core, and the shell ratio can be controlled by pH, the content of oxalic acid and the content of ammonium tungstate. A possible formation and growth mechanism is proposed.

Selective photochromism in a self-coated WO/WO homojunction: enhanced solar modulation efficiency, high luminous transmittance and fast self-bleaching rate.

Pursuing excellent photochromic (PC) properties is still a longstanding challenge for energy-efficient smart coatings. Herein, we have prepared a novel series of self-coated crystalline WO-amorphous WO homojunctions by a one-step hydrothermal process, in which oxalic acid was used as a capping agent to prevent polycondensation and the crystallization of [WO]. The as-prepared nanopowders with tight interfaces have a large specific surface area and rich surface electrons, which leads to a dramatic PC property reaching up to ΔT  = 64.

Highly Enhanced Thermochromic Performance of VO Film Using "Movable" Antireflective Coatings.

The VO film with "movable" antireflective (AR) coating was initially designed and successfully prepared to deal with the challenges that VO faced. The "movable" AR layer, including water and other organic solvents, not only endowed VO with active-passive regulation mode but also dramatically enhanced the thermochromic performance. Furthermore, we combined solid and movable antireflection layer for further structural optimization, and the result turned out to be superior to any multilayer structure reported previously.

A plasmonic non-stoichiometric WO homojunction with stabilizing surface plasmonic resonance for selective photochromic modulation.

Here, we fabricated an oxygen-deficient WO3-x crystalline/amorphous homojunction with a strong and tunable localized surface plasmon resonance (LSPR) absorption and realized selective solar modulation over infrared light by controlling the experimental parameters. The homojunction shows good LSPR stability in photochromic cycles, which paves the way to control LSPR applications.

Facile and Low-Temperature Fabrication of Thermochromic CrO/VO Smart Coatings: Enhanced Solar Modulation Ability, High Luminous Transmittance and UV-Shielding Function.

In the pursuit of energy efficient materials, vanadium dioxide (VO) based smart coatings have gained much attention in recent years. For smart window applications, VO thin films should be fabricated at low temperature to reduce the cost in commercial fabrication and solve compatibility problems. Meanwhile, thermochromic performance with high luminous transmittance and solar modulation ability, as well as effective UV shielding function has become the most important developing strategy for ideal smart windows.

Selective and Tunable Near-Infrared and Visible Light Transmittance of MoO Nanocomposites with Different Crystallinity.

In this Communication, we report MoO nanocomposites in which the near-infrared and visible light transmittance can be selectively modulated through the crystallinity. The MoO nanocomposites were fabricated by a hydrothermal method, and their optical properties were characterized by UV-Vis spectrometer. The obtained results proved the possibility to tune the nanocomposite's optical properties in the UV/Visible spectral region: crystalline MoO mainly regulates the near-infrared range (800-2600 nm), and amorphous MoO mainly changes the visible range from 350 nm to 800 nm and MoO , with semi-crystalline structures mainly modulating around 800-1000 nm.