Cement-based photocatalytic composition, which comprises: (a) at least one cement binder; (b) at least one photocatalyst; (c) at least one cellulose ether; (d) at least one fluidizing agent; (e) at least one first calcareous filler in the form of particles of which at least 95% by weight has a size not greater than 100 m; (f) at least one second calcareous filler in the form of particles of which at least 95% by weight has a size not greater than 30 m; (g) at least one silane supported on an inorganic support in the form of powder. Such composition can be employed as a water paint for obtaining wall coatings with very low thickness, in particular the outdoor applications, which ensure a high and stable photocatalytic effect over time even with relatively low quantities of photocatalyst, generally lower than 10% by weight, with optimal results in terms of uniformity of the coating and resistance of the same to weathering agents.

The construction system includes a composition that includes Portland cement, nano-TiO.sub.2, and slag cement. The composition may also include water. The composition is cured via a CO.sub.2 curing process to produce a self-cleaning photocatalytic composite with lower carbon footprint and may be more economically manufactured than known cement-based photocatalytic composites. The unveiled synergistic effect of using slag cement and applying a CO.sub.2 curing process may reduce the porosity of the material and reduce the penetration of the pollutants that will accumulate in the surface. Thus, pollutants will be more exposed to UV light and decompose the pollutants in a greater rate. The construction system is self-cleaning in that water, such as from rainfall, may effectively clean the cured composition to reset the sequestering capabilities for the construction system to continue to remove toxic gases for the atmosphere.

Disclosed embodiments concern a composition comprising a diatom frustule and two or more photocatalytic nanoparticles dispersed on the surface of the frustule. Also disclosed are embodiments of a method for making the composition. The nanoparticles are dispersed such that they are separate and not in physical contact with each other. An average distance between the nanoparticles may be from greater than 0 nm to 100 nm. The nanoparticles may comprise a dopant material. Paint compositions comprising the diatom frustule compositions are also contemplated. The diatom frustule composition may be useful for removing and/or degrading volatile organic compounds, such as those present in the atmosphere.

The invention relates to photocatalytic compositions, e.g. cement-based photocatalytic compositions, and the uses thereof for obtaining water paints. There is provided a photocatalytic composition, which comprises: (a) at least one inorganic binder; (b) at least one photocatalyst; (c) at least one cellulose with very low viscosity; (d) at least one fluidizing agent; (e) at least one first calcareous filler in the form of particles of which at least 95% by weight has a dimension not greater than 40 m; (f) at least one second calcareous filler in the form of particles of which at least 95% by weight has a dimension not greater than 20 m; (g) at least one thermal insulator material comprising hollow ceramic spheres with sub-mm diameters, and (h) glass bubble borosilicate microspheres.

Bismuth oxyhalide-added building materials are disclosed. The building material is a binder-containing building material, which sets and harden when mixed with water, such as gypsum and cement-based building material. Methods for applying bismuth oxyhalidecomprising coatings onto surfaces of building materials, to protect them against pollutants, are described.

A photocatalytic composition comprising: (a) at least one aerial binder; (b) at least one photocatalyst; (c) at least one cellulose ether; (d) at least one fluidizing agent; (e) at least one pumice in the form of micronized powder; (f) at least one barite in the form of micronized powder. This composition can be used as water-based paint for preparing wall coatings having a very low thickness, in particular for interior applications, which guarantee a high photocatalytic effect and stable with time, even with relatively low quantities of photocatalyst, normally lower than 10% by weight. This coating also has marked inhibitory properties with respect to the growth of mold and bacteria on wall surfaces.

Aim of the present invention is to obtain cementitious products having smooth, planar surfaces and low thickness for applications having aesthetic purpose, of integrated architecture or as substrates, for example for a thin-film photovoltaic unit, with controlled curling and surface roughness, manufactured by mold casting of a fluid composition comprising: I. a hydraulic binder; II. one or more aggregates; III. an anti-shrinkage agent; IV. a superplasticizer agent; V. water, wherein the percentage by weight of said hydraulic binder in the composition is lower than that of said aggregates, and wherein said aggregates have a maximum diameter d.sub.max not greater than one third of the thickness of the product, the final product thus having an arithmetic mean surface roughness Ra not greater than 500 nm and curling not greater than 1500 micron.

Disclosed is a sanitary ware having a photocatalyst layer which has excellent durability even in an environment where the photocatalyst layer is exposed to an acid and an alkali alternately. The sanitary ware comprises a glaze layer, an intermediate layer provided on the glaze layer, and a photocatalyst layer provided on the intermediate layer, wherein the photocatalyst layer comprises titanium oxide in the amount of 95 mass % to 75 mass % and zirconium oxide in the amount of 5 mass % to 25 mass % and the intermediate layer comprises silica in the amount of 98 mass % to 85 mass %, and titanium oxide and/or zirconium oxide in the amount of 2 mass % to 15 mass %.

A composite ultra-high-performance concrete mixture includes cement in an amount between 500 and 680 kg/m.sup.3; a photocatalyst in amount between 10 and 30 kg/m.sup.3; a recycled glass white nano-silica in amount 40 and 60 kg/m.sup.3; calcinated kaolin in amount 70 to 120 kg/m.sup.3; a filler in amount between 200 and 300 kg/m.sup.3; a fine sand in amount between 600 to 970 kg/m.sup.3; and a coarse sand in amount between 400 to 600 kg/m.sup.3.

A photocatalytic powdered water based paint is described comprising photocatalytic binding cement, inert micronized limestone, low viscosity cellulose, fluidifying agent, anti-foaming agent, vinyl polymer and pigments. The water based paint is characterized by the fact of comprising at least one and preferably all the following further additives: metakaolin, titanium dioxide, calcium formate and kieselguhr.