A nanostructure is provided that in one embodiment includes a cluster of cylindrical bodies. Each of the cylindrical bodies in the cluster are substantially aligned with one another so that their lengths are substantially parallel. The composition of the cylindrical bodies include tungsten (W) and sulfur (S), and each of the cylindrical bodies has a geometry with at least one dimension that is in the nanoscale. Each cluster of cylindrical bodies may have a width dimension ranging from 0.2 microns to 5.0 microns, and a length greater than 5.0 microns. In some embodiments, the cylindrical bodies are composed of tungsten disulfide (WS.sub.2). In another embodiment the nanolog is a particle comprised of external concentric disulfide layers which encloses internal disulfide folds and regions of oxide. Proportions between disulfide and oxide can be tailored by thermal treatment and/or extent of initial synthesis reaction.

A method for manufacturing a tungsten trioxide/silicon nanocomposite structure includes steps as follows. A silicon substrate is provided, wherein a surface of the silicon substrate is formed with a plurality of microstructures. A tungsten trioxide precursor solution is provided, wherein the tungsten trioxide precursor solution is contacted with the silicon substrate. A hydrothermal synthesis step is conducted, wherein the tungsten trioxide precursor solution is reacted to form a plurality of tungsten trioxide particles on the plurality of microstructures, so as to obtain the tungsten trioxide/silicon nanocomposite structure.

A method for manufacturing a tungsten trioxide/silicon nanocomposite structure includes steps as follows. A silicon substrate is provided, wherein a surface of the silicon substrate is formed with a plurality of microstructures. A tungsten trioxide precursor solution is provided, wherein the tungsten trioxide precursor solution is contacted with the silicon substrate. A hydrothermal synthesis step is conducted, wherein the tungsten trioxide precursor solution is reacted to form a plurality of tungsten trioxide particles on the plurality of microstructures, so as to obtain the tungsten trioxide/silicon nanocomposite structure.

An electrochromic device comprising a substrate, a set of electrodes disposed on or within the substrate, and a layer comprising ε-WO3 disposed in electrical communication with the set of electrodes, wherein the layer of ε-WO3 exhibits polarization switching are described. Methods of making and using the electrochromic devices are also described. The electrochromic devices are used for detecting acetone in a fluid. The observed change in color of the ε-WO3 layer can be correlated with a subject's medical condition, such as diabetes.

An electrochromic device comprising a substrate, a set of electrodes disposed on or within the substrate, and a layer comprising ε-WO3 disposed in electrical communication with the set of electrodes, wherein the layer of ε-WO3 exhibits polarization switching are described. Methods of making and using the electrochromic devices are also described. The electrochromic devices are used for detecting acetone in a fluid. The observed change in color of the ε-WO3 layer can be correlated with a subject's medical condition, such as diabetes.

A preparation method for a W—Cu composite plate with a Cu phase in finger-shaped gradient distribution is provided. The method includes adding WO.sub.X powder obtained with ammonium metatungstate as a raw material into W powder through a combustion synthesis method, adding a binder and a pore-forming agent to prepare a slurry, then performing tape casting, soaking in water and sintering to obtain a W framework with pores in finger-shaped distribution, and then infiltrating Cu to obtain a target product. The Cu phase in the W—Cu composite material prepared by the present method is distributed in a finger-shaped gradient manner from an infiltration surface to the interior of a specimen, the Cu phase and the W phase are mutually pinned, and the W—Cu interface has good bonding strength. The present method has the characteristics of adjustable material component performance, simple process, low cost, suitability for large-scale production and the like.

A preparation method for a W—Cu composite plate with a Cu phase in finger-shaped gradient distribution is provided. The method includes adding WO.sub.X powder obtained with ammonium metatungstate as a raw material into W powder through a combustion synthesis method, adding a binder and a pore-forming agent to prepare a slurry, then performing tape casting, soaking in water and sintering to obtain a W framework with pores in finger-shaped distribution, and then infiltrating Cu to obtain a target product. The Cu phase in the W—Cu composite material prepared by the present method is distributed in a finger-shaped gradient manner from an infiltration surface to the interior of a specimen, the Cu phase and the W phase are mutually pinned, and the W—Cu interface has good bonding strength. The present method has the characteristics of adjustable material component performance, simple process, low cost, suitability for large-scale production and the like.

According to one embodiment, a tungsten oxide material containing potassium is provided. The tungsten oxide material has a shape of particles including a central section and a peripheral section adjacent to the central section, and having an average particle size of 100 nm or less. A periodicity of a crystal varies between the central section and the peripheral section. In addition, a tungsten oxide powder mass for an electrochromic device including 80% by mass to 100% by mass of the tungsten oxide material is provided. Moreover, a slurry for producing an electrochromic device containing the above tungsten oxide material is provided.

A near-infrared absorbing material fine particle dispersion, a near-infrared absorber laminate, and a laminated structure for near-infrared absorption can exhibit higher near-infrared absorption property, compared to near-infrared fine particle dispersions, near-infrared absorber laminates, and laminated structures for near-infrared absorption, containing tungsten oxides or composite tungsten oxides according to the conventional art. Also, a near-infrared absorbing material fine particle dispersion in which composite tungsten oxide fine particles, each particle containing a hexagonal crystal structure, and a polymer compound with maleic anhydride introduced therein are contained in the polypropylene resin, and the near-infrared absorber laminate and the laminated structure for near-infrared absorption using the dispersion.

A near-infrared absorbing material fine particle dispersion, a near-infrared absorber laminate, and a laminated structure for near-infrared absorption can exhibit higher near-infrared absorption property, compared to near-infrared fine particle dispersions, near-infrared absorber laminates, and laminated structures for near-infrared absorption, containing tungsten oxides or composite tungsten oxides according to the conventional art. Also, a near-infrared absorbing material fine particle dispersion in which composite tungsten oxide fine particles, each particle containing a hexagonal crystal structure, and a polymer compound with maleic anhydride introduced therein are contained in the polypropylene resin, and the near-infrared absorber laminate and the laminated structure for near-infrared absorption using the dispersion.