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.

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.

Provided herein is a cementitious composition comprising a photoactivator, wherein the photoactivator is capable of converting NOx to NO.sub.2 or NO.sub.3 when exposed to ultraviolet (U.V.) or visible light.

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 method for producing photocatalytic mortar includes providing a mortar-producing material including a fine aggregate and cement, a reactant mixture including a zinc source and urea, and a microorganism-containing mixture including water and a urease-producing microorganism, subjecting the microorganism-containing mixture and the reactant mixture to microbial induced precipitation in the mortar-producing material, subjecting zinc carbonate crystal-containing mortar produced to curing for the same to undergo hydration, and subjecting cured mortar to hydrothermal synthesis, so that zinc carbonate crystals therein are converted to nano zinc oxide crystals.