Photocatalysis is the natural phenomenon in which a substance, called photocatalyst through the action of light (natural or artificial) changes the speed of a chemical reaction. The major applications use photocatalysts based on titanium dioxide (TiO2) which needs to be exposed to UV light to activate.

THE NEW ACTIVE PHOTOCATALYST IN THE VISIBLE LIGHT SPECTRUM – The development of a new photocatalyst based on WO3 has significantly increased the effectiveness of photocatalysis and eliminated the problem of using UV light. When exposed to light, in the visible spectrum, WO3 absorbs and converts light energy into electrons and electron holes. WO3 in contact with oxygen and water (the humidity of the air) is thus able to generate reactive oxygen compounds (ROS) and other very aggressive ionic species.

Billions of these highly oxidizing species are created in billionths of a second and work to break down matter at the molecular level. The result is an effective  decomposition of organic and inorganic pollutants  (such as nitrogen oxides, sulfur dioxide, carbon monoxide)  organic  (such as volatile organic compounds such as benzene, toluoene, ethylbenzene , formaldehyde, acetaldehyde, methanol, ethanol, etc.) and finally of  microorganisms  such as microbes, bacteria and viruses).

The strong oxidative power makes it possible to use the photocatalyst based on tungsten trioxide (WO3) as a   photocatalytic disinfectant .

Although many studies have been reported on the photocatalytic inactivation of bacteria, few studies have addressed the inactivation of viruses.

Below we intend to take stock of the effects deriving from the use of photocatalytic solutions against viruses.

Effectiveness  against Viruses including Coronavirus :-

All our devices with the application of the KtV filter allow to pursue the objectives of improving indoor air quality and maintaining it, while at the same time allowing the containment or slowdown of the transmission of Virus.

Our KtV Technology has been test and is effective against Sars-Cov-2. Within 10 minutes the viral load is deactivated by 98.2% and complete deactivation within 30 minutes.  Tests have been performed in reputed European Lab and University.

The studies relating to the transformation of viruses through photocatalysis were performed in an aqueous or liquid environment or with a direct organism / surface contact method and we can speak of two levels of photocatalytic attack:

  • DECOMPOSITION / KILLING of viral cells with resulting STERILIZING effect

The mechanism of inactivation of viruses by photocatalysis is still to be definitively clarified, although the effectiveness of the system has already been demonstrated with laboratory tests, using numerous types of microorganisms and having also quantified the almost complete result of the attack.

This appears to be initiated on the virus particles through their absorption on the catalyst surfaces followed by the attack on the protein capsid and the virus binding sites (direct Redox type attack). According to other sources, the inactivation behavior of viruses is mediated by hydroxyl radicals • O2 – and OH • or also (and in addition) by Reactive Oxygen Species (ROS) such as • O2 -, OH- H2O • HO and free in the mass phase and not from those linked to the surface of the catalyst. The mechanism of subsequent decomposition involves the degradation of the cell wall and cytoplasmic membrane, again due to the production of reactive oxygen species (ROS). This initially leads to the leakage of the cellular content, then to cell lysis, up to a complete mineralization of the organism.

While having to take into account the environmental conditions at the interface, the reactive species have a radius of action that has been estimated to be around 2 mm from the active surface.