 These photocatalytic materials facilitate the oxidative mineralisation of organic and inorganic species by ambient oxygen on their surfaces, rendering the surfaces clean and, usually, hydrophilic.In most commercial photocatalytic products the active layer is a thin, clear, colourless coating of the semiconductor anatase titania, which requires UV light to photogenerate the necessary electrons (e−) and holes (h+), in its conductance and valence bands, respectively, to promote the photocatalytic process.A schematic of the key processes behind the photocatalytic mineralisation of an organic pollutant on the surface of a titania photocatalyst film is illustrated in figure 1 and the overall reaction is summarised by