abstract |
A building material that comprises natural stone, a first photocatalytic layer of titanium dioxide (TiO2), which covers all or only part of the surface of the natural stone and a second layer of a material, selected from the group consisting of: a metal, a metal alloy, titanium nitride (TiN) and titanium carbonitride (TiCN), which covers all or only part of the surface of the first photocatalytic layer. |