Titanium refractive index. In1972 Doctors Fujishima and Honda published

Titanium Dioxide (TiO2) is the naturally occurring oxide of Titanium. Titanium Dioxide is themost widely used white pigment because of its brightness and very high refractive index. In1972 Doctors Fujishima and Honda published a paper on their discovery of photocatalyticsplitting of water on Titanium Dioxide (TiO2) electrodes. This event marked the beginning of anew era in heterogeneous photo catalysis. Biologically inert, TiO2 is used for water and airpurification, for medical use, as pigments in foodstuffs, paints, ceramics, cosmetics orpharmacology, as a corrosion resistant coating, self-cleaning coatings and antifogging in solarcells for the production of hydrogen and electric energy, in electronic devices and as gassensor.The photocatalytic properties of titanium dioxide lead to the creation of hydroxyl radicals that willbreakdown organic compounds that comprise a built up roofing system. It is important tounderstand the electro-chemical progression from the application of the KST-63-300 roofcoating to the eventual roof failure. Sunlight activates the titanium dioxide in the roof coatingcreating hydroxyl radicals.Hydroxyl radicals, which are free radical aremolecules with an unpaired electron. The photocatalysis activated by the sunlight and facilitatedby Titanium Dioxide has the ability to createelectron-hole pair which in turn enables a oneelectronoxidation step with water to producehydroxyl radicals (.OH).H2O+H+ ?.OH+H+Oxygen can act as an electron acceptor, and betransformed by the promoted electron in theconductive band to form superoxide ion (O2-).The superoxide ion is a highly reactive particle,able to oxidize organic materials. Above is anoutline of the electro-chemical process that creates the hydroxyl radical. In simple terms,sunlight activates the titanium dioxide in the roof coating, in-turn the titanium dioxide reacts byproducing an electrical charge that breaks the bonds of water molecules, one of the

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