A system for creating targeted vanadium oxide (VO.sub.2) nanoparticle compositions comprising a stock reaction mixture that is a fluid combination of at least one vanadium source combined with at least one dopant source. Each dopant source contains at least one target dopant element. The ratio of the number of vanadium atoms in the vanadium source to the number of target dopant element atoms in the dopant source is less than or equal to 10:1. A solvent that is compatible with said stock reaction mixture is selected. A pressure regulator increases the pressure of the solvent and the stock reaction mixture to between 0 and 5,000 psi. A heating element increases the temperature of the solvent to between 50 and 500° C. A mixing unit receives and mixes a continuous flow of stock reaction mixture with solvent to heat the stock reaction mixture and initiate formation of the targeted vanadium oxide (VO.sub.2) nanoparticle composition.

The present invention is directed to methods of preparing metal sulfide, metal selenide, or metal sulfide/selenide nanoparticles and the products derived therefrom. In various embodiments, the nanoparticles are derived from the reaction between precursor metal salts and certain sulfur- and/or selenium-containing precursors each independently having a structure of Formula (I), (II), or (III), or an isomer, salt, or tautomer thereof, where Q.sup.1,Q.sup.2,Q.sup.3,R.sup.1,R.sup.2,R.sup.3,R.sup.5, and X are defined within the specification.

Filled carbon nanotubes (CNTs) and methods of synthesizing the same are provided. An in situ chemical vapor deposition technique can be used to synthesize CNTs filled with metal sulfide nanowires. The CNTs can be completely and continuously filled with the metal sulfide fillers up to several micrometers in length. The filled CNTs can be easily collected from the substrates used for synthesis using a simple ultrasonication method.

A method of preparing iron oxide nanoparticles using an herbal mixture comprising Capparis spinosa, Cichorium intybus, Solanum nigrum, Cassia occidentalis, Terminalia arjuna, Achillea millefolium, and Tamarix gallica. The method produces crystalline γ-Fe.sub.2O.sub.3 nanoparticles which are superparamagnetic. The iron oxide nanoparticles are used in a method of killing or inhibiting the growth of a bacteria and/or fungus, particularly in the form of a biofilm. The nanoparticles are also used in a method of treating colon cancer.

Provided is a method for producing a phosphor, using a nitride raw material, that gives a high-reliability (Sr,Ca)AlSiN.sub.3-based nitride phosphor at a productivity higher than before. The method comprises a mixing step of mixing raw materials and a calcining step of calcining the mixture obtained in the mixing step and, in producing the phosphor having a crystalline structure substantially identical with that of (Sr,Ca)AlSiN.sub.3 crystal as the host crystal, a strontium nitride containing SrN, Sr.sub.2N, or the mixture thereof as the main crystalline phase, as determined by crystalline phase analysis by powder X-ray diffractometry, and having a nitrogen content of 5 to 12 mass % is used as part of the raw materials.

Quantum dot semiconductor nanoparticle compositions that incorporate ions such as zinc, aluminum, calcium, or magnesium into the quantum dot core have been found to be more stable to Ostwald ripening. A core-shell quantum dot may have a core of a semiconductor material that includes indium, magnesium, and phosphorus ions. Ions such as zinc, calcium, and/or aluminum may be included in addition to, or in place of, magnesium. The core may further include other ions, such as selenium, and/or sulfur. The core may be coated with one (or more) shells of semiconductor material. Example shell semiconductor materials include semiconductors containing zinc, sulfur, selenium, iron and/or oxygen ions.

A method of synthesizing bimetallic oxide nanocomposites includes the steps of: providing a first metal salt solution; adding an oxidizing agent to the first metal salt solution while degassing the solution with an inert gas; heating the first metal salt solution; adding a second metal salt solution to the heated first metal salt solution to form a reaction mixture; adding a solution comprising a poly (ionic liquid) into the reaction mixture; adding a first base into the reaction mixture; adding a second base while stirring and maintaining a temperature ranging from about 40° C. to about 65° C. to provide a solution including a bimetallic oxide nanocomposite precipitate. The first metallic salt solution can include FeCl.sub.3 dissolved in water. The second metallic salt solution can include CuCl.sub.2 dissolved in water. The bimetallic oxide nanocomposites can be combined with epoxy resin to coat a steel stubstrate.

Methods and systems for optical effects in pigments, inks, and on media. One aspect of this disclosure involves a pigment particle which includes a core, having a fluorescent material and having a spherical shape, and a shell surrounding the core; the shell includes a photochromic material which has a first optical property in a first light source and a second optical property in a second light source which includes a set of wavelengths not sufficiently present in the first light source. The second optical property attenuates an emitted radiation from the fluorescent material. Other aspects are also described.

Ion conductive organic-inorganic composite particles are particles that have an organic group on the surface of inorganic particles and have at least a configuration that does not allow the inorganic particles to contact with each other by steric hindrance of the organic group, the organic group containing an ion conductive group.

Provided herein are TiO.sub.2-x nanoparticles and materials that show unusual photophysical and optical properties. These TiO.sub.2-x particles and materials can be used as efficient photocatalysts for the reduction of CO.sub.2 with H.sub.2O to produce CH.sub.4. Also provided herein are methods of making TiO.sub.2-x nanoparticles using a polymer-derived mesoporous carbon (PDMC) as a template.