Nanotech

A Czech firm has recently started producing a powerful photocatalytic paint that cleans the air of cigarette smoke, viruses and bacteria in minutes, whilst the Czech Academy of Sciences has just opened a new nanocenter to spearhead research into practical applications for nanoscience.

"This is an exciting time for science - something like a revolution," said Jiri Rathousky, the project's leader, as he demonstrated a contraption called a dip coater in the lab of the newly-opened center.

The center – aided by funding from the European Union – is the pride and joy of the Heyrovsky Institute of Physical Chemistry, a rather drab concrete tower block in the northern suburbs of Prague. Hidden away on the sixth floor, Rathousky and his colleagues in white overalls are doing some truly remarkable things with very small materials.

The magic of photocatalysts

"For example here we coat sheets of glass with a thin layer of a nanostructure called titanium dioxide," Rathousky explained.

"Titanium dioxide is a very efficient photocatalyst, and in this way, we obtain a photocatalytically active surface. This type of photocatalytically active surface can be used for example in air-conditioning, for cleaning the air, and for removal of pollutants by the action of light."

Photocatalysts, substances that speed up a chemical reaction when light hits them, have tremendous practical uses like sterilization and air cleansing.

In a small, rather dilapidated factory on the outskirts of Prague, a company called Advanced Materials is putting titanium dioxide to use in something called photocatalytic paint, an incredibly clever, virtually translucent paint that actually cleans the air in your living room of everything from bacteria to cigarette smoke.

"Even in a concentration of one cigarette per cubic metre, you see very high degradation rate," said Jan Prochazka, Advanced Materials' co-owner. In one hour, he said, a cubic meter box used to test the paint is clean of cigarette smoke.

"We say [the paint will oxidize] ninety percent of all contaminants in 24 hours, but it's much faster. It's just to stay on the safe side," Prochazka added.

Molecular reaction

The tiny titanium dioxide molecules in the paint react to UV rays in sunlight or special lamps, oxidizing everything from carcinogens to allergens to dust mites. That means that titanium oxide molecules react with smoke or bacteria, essentially consuming it. That leaves a by-product of water and carbon dioxide, which are harmless.

Photocatalytic paint has been around for a while, but he says that their new technique has been refined to be hundreds of times more powerful and efficient, and could revolutionize the way air is cleaned in homes and offices.

However, this technique is still relatively new, and a 2008 study from the Lawrence Berkeley National Laboratory in the US found that photocatalytic oxidization may increase the presence of formaldehyde, a potentially dangerous chemical, in a real-life, indoor setting.

Undeterred, Advanced Materials is already shipping their product to Spain, South Africa and New Zealand, and licences to make it in other countries are already being drawn up.

The success of Advanced Materials and the creation of the Nanocentre in Prague have led some in the Czech media to speak of the Czech Republic as having the potential to become a major force in nanotechnology in Europe.

Huge growth ahead

But perhaps all of this trumpeting should be taken with a pinch of salt.

"Nanotech is the new oil industry," said Dean Freeman, a nanotech industry analyst with Gartner Research.

"There are many opportunities in the nanotech space for research. The key is making a product that can get traction and be sold commercially. From a research perspective I have not seen a great deal on nanotech from the Czech Republic. [But that] could have more to do with how publicized any research is."

However he added their success in accessing EU funds for nanotech projects – and the Czech government's commitment – certainly placed the Czechs in a strong position to make a name for themselves on the global nanotech market.

Author: Rob Cameron, Prague
Editor: Ben Knight