A dispersion liquid contains fine particles of core-shell type inorganic oxide that have high dispersion stability and transparency and allow for excellent light resistance and weather resistance by being mixed in a coating film. The fine particles are produced by treating the surfaces of (a) fine particles of titanium-containing metal oxide serving as core particles with a hydrate and/or an oxide of a metal element such as zirconium to provide surface-treated particles or fine particles of titanium-containing metal oxide having (b) an intermediate layer and by covering the surfaces of the surface-treated particles to form (c) a shell layer with a composite oxide of silicon and at least one metal element selected from aluminum, zirconium, and antimony.

The present invention relates to a dispersion liquid of titanium oxide-tungsten oxide composite photocatalytic fine particles that is characterized by having two types of photocatalytic fine particles dispersed in an aqueous dispersion medium, the fine particles including i) fine particles of titanium oxide that contain a peroxotitanium component and a copper component and ii) fine particles of tungsten oxide. The present invention can provide a dispersion liquid and the like that can be used to conveniently manufacture a photocatalytic thin film that demonstrates photocatalytic activity even within visible light (400-800 nm) only, exhibits high antibacterial performance, is highly durable, and wherein the state of copper coordination is stable against exposure to heat and ultraviolet rays and is not easily modified. The dispersion liquid is a dispersion liquid of titanium oxide-tungsten oxide composite photocatalytic fine particles that contains copper-containing titanium oxide fine particles.

The present invention relates to a dispersion liquid of titanium oxide-tungsten oxide composite photocatalytic fine particles that is characterized by having two types of photocatalytic fine particles dispersed in an aqueous dispersion medium, the fine particles including i) fine particles of titanium oxide that contain a peroxotitanium component and a copper component and ii) fine particles of tungsten oxide. The present invention can provide a dispersion liquid and the like that can be used to conveniently manufacture a photocatalytic thin film that demonstrates photocatalytic activity even within visible light (400-800 nm) only, exhibits high antibacterial performance, is highly durable, and wherein the state of copper coordination is stable against exposure to heat and ultraviolet rays and is not easily modified. The dispersion liquid is a dispersion liquid of titanium oxide-tungsten oxide composite photocatalytic fine particles that contains copper-containing titanium oxide fine particles.

In one aspect of the invention, a dye sensitized solar cell has a counter-electrode including carbon-titania nanocomposite thin films made by forming a carbon-based ink; forming a titania (TiO.sub.2) solution; blade-coating a mechanical mixture of the carbon-based ink and the titania solution onto a substrate; and annealing the blade-coated substrate at a first temperature for a first period of time to obtain the carbon-based titania nanocomposite thin films. In certain embodiments, the carbon-based titania nanocomposite thin films may include solvent-exfoliated graphene titania (SEG-TiO.sub.2) nanocomposite thin films, or single walled carbon nanotube titania (SWCNT-TiO.sub.2) nanocomposite thin films.

In one aspect of the invention, a dye sensitized solar cell has a counter-electrode including carbon-titania nanocomposite thin films made by forming a carbon-based ink; forming a titania (TiO.sub.2) solution; blade-coating a mechanical mixture of the carbon-based ink and the titania solution onto a substrate; and annealing the blade-coated substrate at a first temperature for a first period of time to obtain the carbon-based titania nanocomposite thin films. In certain embodiments, the carbon-based titania nanocomposite thin films may include solvent-exfoliated graphene titania (SEG-TiO.sub.2) nanocomposite thin films, or single walled carbon nanotube titania (SWCNT-TiO.sub.2) nanocomposite thin films.

Virus multilayers can be used as templates for growth of inorganic nanomaterials. For example, layer-by-layer construction of virus multilayers on functionalized surfaces form nanoporous structures onto which metal particles or metal oxide nanoparticles can be nucleated to result in an interconnected network of nanowires.

Virus multilayers can be used as templates for growth of inorganic nanomaterials. For example, layer-by-layer construction of virus multilayers on functionalized surfaces form nanoporous structures onto which metal particles or metal oxide nanoparticles can be nucleated to result in an interconnected network of nanowires.

A titanium oxide powder of the present invention has a BET specific surface area of 5 m.sup.2/g or more and 15 m.sup.2/g or less and contains polyhedral-shaped titanium oxide particles having eight or more faces, in which a mass reduction rate in a case of being heated at 800° C. for 1 hour in an air atmosphere is 0.03% by mass or more and 0.5% by mass or less.

The present invention relates to a process for preparing high aspect ratio titanium dioxide (TiO.sub.2) nanorods using a one-pot hydrothermal technique. Reaction additives of oxalic acid and sodium hydroxide (NaOH) are used to promote the conversion of titanium dioxide precursors, preferably tetraisopropoxide (TTIP), into a one-dimensional TiO.sub.2 morphology.

The present invention relates to a process for preparing high aspect ratio titanium dioxide (TiO.sub.2) nanorods using a one-pot hydrothermal technique. Reaction additives of oxalic acid and sodium hydroxide (NaOH) are used to promote the conversion of titanium dioxide precursors, preferably tetraisopropoxide (TTIP), into a one-dimensional TiO.sub.2 morphology.