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Vertically-aligned WO₃ nanoplates on transparent conducting fluorine-doped tin oxide (FTO) glass were prepared by a facile template-free crystal-seed-assisted hydrothermal method. The effects of the hydrothermal temperature and reaction time on the crystal structure and morphology of the products were investigated by XRD and SEM. The XRD results showed that the as-prepared thin films obtained below 150${}^{\circ }$C comprised orthorhombic WO₃ ⋅ H₂O and completely converted to monoclinic WO₃ at 180${}^{\circ }$C. It was also noted that there was a phase transformation from orthorhombic to monoclinic by increasing the reaction time from 1 to 12 h. SEM analysis revealed that WO₃ thin films are composed of plate-like nanostructures.

Tungsten trioxide (WO${}_3)$ nanostructures were synthesized by a simple hydrothermal method. The morphology of WO₃ nanostructures can be varied by adding inorganic ions from alkali metal salts. The effect of inorganic ions on the microstructure and visible-light-driven photocatalytic activity was characterized via X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and UV-vis spectroscopy. Methylene blue (MB) photodegradation experiments showed that the one-dimensional (1D) WO₃ nanorods prepared by the aid of potassium sulfate exhibited the highest photocatalytic efficiency (96.4% in 2.5 h) under visible light irradiation. It is deduced that the excellent photocatalytic property of 1D WO₃ nanorods was mainly attributed to the efficient charge transfer capability, which is promising for practical applications in environmental remediation.

This paper presents the first report of the excellent oxygen reduction activity and durability of a composite structure that consists of highly active V₂O₅-WO₃ electrocatalyst. Outstanding electrocatalytic performance toward oxygen reduction under alkaline medium was achieved by selecting a highly active and optimum concentration of V₂O₅ on WO₃ composite. In particular, the excellent catalytic activity of the 25 wt.% V₂O₅ with 75 wt.% WO₃(WV${}^{-1})$ catalyst for oxygen reduction reaction (ORR) can be attributed to the optimum concentration of V₂O₅, high surface area, high conductivity, and mesoporous nature, since they aid facile electrochemical activity and reduced overpotential and small Tafel values than other catalysts. In addition, it exhibits long-term durability.

The Cs${}_{0.3}$WO₃/WO₃ composite with near-infrared shielding properties was synthesized by the solvothermal method using tungstic acid and cesium salt as raw materials. The as-prepared composites were tested by X-ray powder diffraction, scanning electron microscopy, energy spectrum analysis, transmission electron microscopy, electron energy loss spectroscopy, and ultraviolet-visible near-infrared spectroscopy. The effects of different reaction conditions on the structure and near-infrared shielding properties of the synthesized composites were investigated. The best near-infrared light transmittance of as-prepared composites can reach up to 9%, which provides a feasible solution for the near-infrared shielding material. The new homogeneous composites of cesium tungsten bronze and tungsten oxide are good candidates for solar filters.

In the multicolor regulation of visible-light band, the inorganic electrochromic multicolor modulation has always been the bottleneck of expanding the application of inorganic electrochromic reflection display. An electrochromic device (ECD) based on an ultracompact unsymmetric Fabry–Perot resonator was designed. Electrochromic oxides such as tungsten oxide, offer the possibility to tune their refractive index and extinction coefficient upon ion insertion, allowing active control over resonance conditions for Fabry–Perot cavity-type devices. The spectrum colors of red, yellow, green and blue can be obtained by adjusting the thickness of tungsten oxide in the W/(WO${}_{3-x}\cdot \mathit{\text{n}}$H₂O) electrode. The optical constants of tungsten oxide can be adjusted reversibly by using electrochemical ion insertion/stripping, and the reflection peak of W/(WO${}_{3-x}\cdot n$H₂O) electrode in the visible-light band can be adjusted. The dynamic color control of the ECDs can be achieved finely.

WO₃-incorporated C–TiO₂ nanotubes were successfully fabricated using radio frequency sputtering technique. The effects of sputtering powers on the nanotube morphology, crystal structure, optical properties and visible photoresponse were investigated. Lattice substitution of WO₃ species within the lattice of C–TiO₂ nanotubes has an important function in maximizing the photocurrent generation. WO₃-incorporated C–TiO₂ nanotubes exhibit good visible photoresponse compared with C–TiO₂ nanotubes. The interpretation of interband states has an important function in improving photoinduced electron transport.

In this work, ${\mathrm{\text{WO}}}_3$ quantum dots grow in situ on the synthesized ultra-thin ${\mathrm{\text{g-C}}}_3{\mathrm{\text{N}}}_4$ nanosheets, ultimately forming a type of tightly bound 2D/0D Z-type heterojunctions. It was found that ${\mathrm{\text{WO}}}_3$ quantum dots were closely combined with ${\mathrm{\text{g-C}}}_3{\mathrm{\text{N}}}_4$ nanosheets through SEM and TEM measurements. XRD, IR, and XPS characterization proved a ${\mathrm{\text{g-C}}}_3{\mathrm{\text{N}}}_4/{\mathrm{\text{WO}}}_3$ heterojunction material was formed. The construction of ${\mathrm{\text{g-C}}}_3{\mathrm{\text{N}}}_4/{\mathrm{\text{WO}}}_3$ heterojunctions enhanced visible light absorption, improved carrier separation efficiency, and reduced charge transfer resistance. Photocatalytic hydrogen production tests showed that the hydrogen production rate of 20% ${\mathrm{\text{g-C}}}_3{\mathrm{\text{N}}}_4/{\mathrm{\text{WO}}}_3$ composite materials was 2.8 times that of the original ${\mathrm{\text{g-C}}}_3{\mathrm{\text{N}}}_4$, and the hydrogen production amount within 3h was 3.7 times that of the original ${\mathrm{\text{g-C}}}_3{\mathrm{\text{N}}}_4$. Photocatalytic degradation of Rhodamine B and 4-chlorophenol under visible light irradiation showed that compared with ${\mathrm{\text{g-C}}}_3{\mathrm{\text{N}}}_4$, the photocatalytic degradation efficiency of 20% ${\mathrm{\text{g-C}}}_3{\mathrm{\text{N}}}_4/{\mathrm{\text{WO}}}_3$ composite materials was enhanced. The results reveal that the special structured ${\mathrm{\text{g-C}}}_3{\mathrm{\text{N}}}_4/{\mathrm{\text{WO}}}_3$ composite materials have excellent photocatalytic activity, which can not only efficiently produce hydrogen but also efficiently degrade organic pollutants, providing an important reference for solving energy crises and environmental problems.

ITO conductive glass is on the basis of sodium calcium or silicon boron based glass, using the method of magnetron sputtering plating a layer of indium tin oxide (commonly known as ITO) film processing. In this paper, by using RF magnetron sputtering method to change the sputtering power, argon oxygen ratio and sputtering time, the electrochromic materials——WO₃ were prepared in different conditions. Under the best conditions (O₂: Ar=9:21, Power=90W, Pressure=1.4Pa, Time=1h), the transmittance of WO₃ thin film of the colored and faded states in the visible light region is more than 80%, and the film has a very good cycle property.