Photocatalytic concrete

Photo-catalytic concrete is a formulation of concrete used as pavers and other structural concrete that includes titanium dioxide (TiO2) as an admixture or superficial layer. Titanium dioxide is a heterogeneous photocatalyst that uses sunlight and moisture to absorb and render oxides of nitrogen (NO and NO2) into nitrate ions (NO3−), which are then either washed away by rain or soaked into the concrete to form stable compounds.

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