"A nano meter is a billionth of a meter. A nano particle compared to a football is like comparing the football to earth."

Nanotechnology is truly an ambiguous field. Nowadays it can be seen in nearly every producing industry and ranges from engineering, computer science, medicine, quantum mechanics, robotics and many more. 

The basic concept of nanotechnology by Norio Taniguchi formulates that a material‘s critical and essential properties are given on a nanometer scale – a phenomenon which can be observed at many occasions in nature all around us, such as the all-known lotus effect or the very detailed structures within bones or shells. 

Focus

TITANIUM DIOXIDE

cityCure deploys unique and patented titanium dioxide coatings for several reasons and several goals and uses. Selfcleaning capacity, airpurification and removal of odour are the three most significant benefits there are, and the easy-to-apply, safe and extremely long durability are some other features of this fantastic coating. Titanium dioxide features are long known. It is only since 2014 that it is possible to actually bond the TiO2 into surfaces.

Titanium dioxide, also known as titanium(IV) oxide or titania, is the naturally occurring oxide of titanium, chemical formula TiO2. When used as a pigment, it is called titanium white, Pigment White 6 (PW6), or CI 77891. Generally it is sourced from ilmenite, rutile and anatase. It has a wide range of applications, from paint to sunscreen to food colouring. When used as a food colouring, it has E number E171.

Titanium dioxide is found in the majority of physical sunscreens because of its high refractive index, its strong UV light absorbing capabilities and its resistance to discolouration under ultraviolet light. This advantage enhances its stability and ability to protect the skin from ultraviolet light. Nano-scaled titanium dioxide particles are primarily used in sun screen lotion because they scatter visible light less than titanium dioxide pigments while still providing UV protection. Sunscreens designed for infants or people with sensitive skinare often based on titanium dioxide and/or zinc oxide, as these mineral UV blockers are believed to cause less skin irritation than other UV absorbing chemicals.

This pigment is used extensively in plastics and other applications not only as a white pigment or an opacifier but also for its UV resistant properties where the powder disperses the light – unlike organic UV absorbers – and reduces UV damage, due mostly to the extremely high refractive index of the particles. Certain polymers used in coatings for concrete or those used to impregnate concrete as a reinforcement are sometimes charged with titanium white pigment for UV shielding in the construction industry, but it only delays the oxidative photodegradation of the polymer in question, which is said to "chalk" as it flakes off due to lowered impact strength and may crumble after years of exposure in direct sunlight if UV stabilizers have not been included .

PHOTOCATALYST

TiO2 fibers and spirals.

Titanium dioxide, particularly in the anatase form, is a photocatalyst under ultraviolet (UV) light. It has been reported that titanium dioxide, when doped with nitrogen ions or doped with metal oxide like tungsten trioxide, is also a photocatalyst under either visible or UV light. The strong oxidative potential of the positive holes oxidizes water to create hydroxyl radicals. It can also oxidize oxygen or organic materials directly. Hence, in addition to its use as a pigment, titanium dioxide can be added to paints, cements, windows, tiles, or other products for its sterilizing, deodorizing and anti-fouling properties and is used as a hydrolysis catalyst. It is also used in dye-sensitized solar cells, which are a type of chemical solar cell (also known as a Graetzel cell).

The photocatalytic properties of titanium dioxide were discovered by Akira Fujishima in 1967 and published in 1972. The process on the surface of the titanium dioxide was called the Honda-Fujishima effect. Titanium dioxide, in thin film and nanoparticle form has potential for use in energy production: as a photocatalyst, it can carry out hydrolysis; i.e., break water into hydrogen and oxygen. With the hydrogen collected, it could be used as a fuel. The efficiency of this process can be greatly improved by doping the oxide with carbon.  Further efficiency and durability has been obtained by introducing disorder to the lattice structure of the surface layer of titanium dioxide nanocrystals, permitting infrared absorption.

In 1995 Fujishima and his group discovered the superhydrophilicity phenomenon for titanium dioxide coated glass exposed to sun light. This resulted in the development of self-cleaning glass and anti-fogging coatings.

TiO2 incorporated into outdoor building materials, such as paving stones in noxer blocks or paints, can substantially reduce concentrations of airborne pollutants such as volatile organic compounds and nitrogen oxides.

A photocatalytic cement that uses titanium dioxide as a primary component, produced by Italcementi Group, was included in Time's Top 50 Inventions of 2008.

Attempts have been made to photocatalytically mineralize pollutants (to convert into CO2 and H2O) in waste water. TiO2 offers great potential as an industrial technology for detoxification or remediation of wastewater due to several factors.

The process uses natural oxygen and sunlight and thus occurs under ambient conditions; it is wavelength selective and is accelerated by UV light.
The photocatalyst is inexpensive, readily available, non-toxic, chemically and mechanically stable, and has a high turnover.
The formation of photocyclized intermediate products, unlike direct photolysis techniques, is avoided.
Oxidation of the substrates to CO2 is complete.
TiO2 can be supported as thin films on suitable reactor substrates, which can be readily separated from treated water.