An electrochromic device comprising a substrate, a set of electrodes disposed on or within the substrate, and a layer comprising -WO3 disposed in electrical communication with the set of electrodes, wherein the layer of -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 -WO3 layer can be correlated with a subject's medical condition, such as diabetes.

A method of making an electrode including dissolving a copper (Cu) salt and benzene-1,3,5-tricarboxylate in a solvent and heating to a temperature of 60 C. to 100 C. to form a framework. Further, the method includes mixing a zinc (Zn) salt and the framework to form a zinc-doped framework and heating the zinc-doped framework to a temperature of 300 C. to 600 C. under air to form ZnCuO nanoparticles. Furthermore, the method includes mixing the ZnCuO nanoparticles, a binding compound, and a conductive carbon compound in a solvent to form a suspension and spraying the suspension onto a substrate with a spray gun using air pressure to form the electrode. The ZnCuO nanoparticles have a spherical shape with an average size of less than 100 nanometers (nm).

A carbon nanotube assembly satisfies at least one of the following conditions (1) to (3): (1) an FT-IR spectrum of a CNT dispersion obtained by dispersing the CNT assembly has a peak based on plasmon resonance of the CNTs in a wave number range of greater than 300 cm.sup.1 and 2000 cm.sup.1 or less; (2) the highest peak in a differential pore capacity distribution of the CNT assembly is located within a pore size range of more than 100 nm and less than 400 nm; and (3) a two-dimensional spatial frequency spectrum of an 10 electronic micrographic image of the CNT assembly has at least one peak within a range of 1 m.sup.1 or more and 100 m.sup.1 or less.

A method of photocatalytic degradation includes contacting a nanocomposite with a solution including one or more pollutants. The nanocomposite is a graphite-phase carbon nitride copper oxide and magnesium aluminum oxide (g-C.sub.3N.sub.4@CuO/MgAl.sub.2O.sub.4) material and includes a graphite-phase carbon nitride (g-C.sub.3N.sub.4) in an amount of 2 to 20 percent by weight (wt. %), copper oxide in an amount of 1 to 10 wt. %, and magnesium aluminum oxide (MgAl.sub.2O.sub.4) in an amount of 75 to 95 wt. % based on a total weight of the g-C.sub.3N.sub.4@CuO/MgAl.sub.2O.sub.4 material. The method further includes irradiating the nanocomposite with light having a wavelength of 400 to 800 nm in the absence of UV light to photocatalytically degrade the one or more pollutants in the solution.

A carbon nanotube assembly satisfies at least one of the following conditions (1) to (3): (1) an FT-IR spectrum of a CNT dispersion obtained by dispersing the CNT assembly has a peak based on plasmon resonance of the CNTs in a wave number range of greater than 300 cm.sup.1 and 2000 cm.sup.1 or less; (2) the highest peak in a differential pore capacity distribution of the CNT assembly is located within a pore size range of more than 100 nm and less than 400 nm; and (3) a two-dimensional spatial frequency spectrum of an electronic micrographic image of the CNT assembly has at least one peak within a range of 1 m.sup.1 or more and 100 m.sup.1 or less.

The epsilon polymorph of vanadyl phosphate, -VOPO.sub.4, made from the solvothermally synthesized H.sub.2VOPO.sub.4, is a high-density cathode material for lithium-ion batteries optimized to reversibly intercalate two Li-ions to reach the full theoretical capacity at least 50 cycles with a coulombic efficiency of 98%. This material adopts a stable 3D tunnel structure and can extract two Li-ions per vanadium ion, giving a theoretical capacity of 305 mAh/g, with an upper charge/discharge plateau at around 4.0 V, and one lower at around 2.5 V.

The present disclosure relates to a process for preparing a lithium salt of bis(fluorosulfonyl)imide (LiFSI) in solid form, wherein the solid form LiFSI salt is extracted from a solution comprising at least one solvent through supercritical fluid extraction. The present invention also relates to the LiFSI in solid form obtained therefrom, as well as the use of such LiFSI in an electrolyte for batteries.

The embodiments of the present disclosure relate to a method and apparatus for producing a carbon nanomaterial product (CNM) product that may comprise carbon nanotubes and various other allotropes of nanocarbon. The method and apparatus employ a consumable carbon dioxide (CO.sub.2) and a renewable carbonate electrolyte as reactants in an electrolysis reaction in order to make CNTs. In some embodiments of the present disclosure, operational conditions of the electrolysis reaction may be varied in order to produce the CNM product with a greater incidence of a desired allotrope of nanocarbon or a desired combination of two or more allotropes.

A composite material comprising carbon nanotubes is described, wherein said composite material does not comprise any carbon nanotube aggregates having a smallest dimension larger than 1 mm. The efficiency of dispersion and anchoring as well as processing capability of the commercially relevant carbon nanotube composites are significantly improved.

A positive electrode active material that inhibits discharge capacity from decreasing during charge and discharge cycles is provided. Alternatively, a secondary battery with a high level of safety is provided. The secondary battery includes a positive electrode containing a positive electrode active material, a negative electrode, and an electrolyte. The positive electrode active material is formed in the following manner: a first composite oxide containing lithium and cobalt, a magnesium source, and a fluoride are mixed to form a mixture; the mixture is heated at higher than or equal to 650 C. and lower than or equal to 1130 C. to form a second composite oxide; and the second composite oxide is cooled down at a temperature decreasing rate higher than 250 C./h.