Imagine a world where every building in each of the world’s major cities benefited from a coating of ecofriendly nanocoating materials. Imagine if each is able to actively decompose the pollutants, which are typically present in its surrounding air. With each building actively contributing to significantly reducing our carbon footprint, the quality of our air will greatly improve. Today, innovations in nanotechnology hold out the prospect of reshaping the future of our built environments ecosystem.
The Science Of Ecofriendly Nanocoating Materials
The innate ability of titanium dioxide (TiO2) to decompose organic pollution has been well known and recognized for over half a century. However, despite that body of knowledge, the practical applications emerging for commercial use have been few and far between. Developing scalable, durable, ecofriendly nanocoating materials has proven to be troublesome and expensive. However, now, a solution to this dilemma may have been discovered.
Titanium dioxide occurs in three naturally occurring forms. Japanese researchers discovered the photocatalytic properties of one of these forms, anatase, in the late 1960s. Under the influence of the ultraviolet-radiation found in sunlight, anatase can decompose commonly found organic pollutants into harmless carbon dioxide. These pollutants include bacteria, fungi, and nicotine, together with some inorganic materials. This is due to the catalytic effect generated through the nanostructure of anatase’s crystals.
Preserving Our Monuments
Applied in outdoor environments, this commercially viable and readily available material could represent an efficient, self-cleaning solution for modern buildings. A chemical reaction generates this self-cleaning solution. This reaction leaves behind a residue on building façades, which rain consequently washes away.
One intriguing aspect of this scientific discovery is the application of these ecofriendly nanocoating materials to monuments. This may ultimately contribute to the preservation of our cultural heritage in our urban environments. These are under threat by a toxic brew of pollutants.
Easier Said Than Done
Unfortunately, photocatalytic paints and additives have long posed a seemingly insurmountable challenge for the materials coating industry. This is mainly due to the catalytic action affecting both the durability of resin binders and its stimulation of the oxidation of the essential components of the paint.
Researchers in Greece are testing a paint called “Kirei,” a name inspired by a Japanese word meaning both clean and beautiful. Given Greece’s extraordinary historical and cultural legacy, unlocking the benefits of ecofriendly nanocoating materials is of paramount importance to restoring its World Heritage class inheritance.
“Kirei,” is an innovative product, thanks to its ability to combine the reflective properties of cool wall paints with the self-cleaning action of photocatalytic nanoparticles. Applied on exterior surfaces, Kirei paint can cause up to 94 percent of the incident infrared radiation (IR) to be reﬂected back into the atmosphere. This will result in energy savings and cost reductions when it comes to heating and cooling. These reﬂection values are enhanced by the paint’s self-cleaning capability. When compared to conventional paints, these new paint formulations remain stable and unchanged for longer.
Renovating Buildings Via A Sustainable And Adaptable Envelope System
The development of Kirei has been part of the European-sponsored BRESAER project. This project is exploring the commercial feasibility of alternative sustainable and adaptable “envelope systems” to renovating buildings and national architectural monuments. The new paint formulation was tested in artificial, accelerated weathering conditions under strict ISO standard laboratory protocols. To date, the results of these tests are encouraging. After 2,000 hours of exposure to the tough, simulated environmental conditions, there was no sign of discolouration, chalking, cracking, or any other paint defects. Based on these test results, the expected service life of the coating is at least ten years.
Decreasing The Effects Of Pollution
Numerous studies are now in the process of fielding to exploit titanium dioxide’s pollution-cleaning properties. Some, on actively decreasing pollution levels as its main focus. Technically, there is no doubt about anatase’s ability to decrease the levels of nitrogen oxides in the surrounding air. However, in real life environmental conditions, there are a host of differences in pollution, wind, light, and temperature that we experience across a range of urban environments.
One such major target for de-pollution is in the confines of traffic tunnels where the quality of air is typically problematic and on roads themselves. Discovering an effective and viable way to strip nitrogen oxides out of the air would make a significant contribution to the quality of our air.
Coming To Fruition
In laboratory conditions, the air is blown over the photocatalytic surface. This creates a certain degree of turbulence in the air flow. This then results in the NOx-particles and the photocatalytic material coming into full contact with one another. However, in live applications, the air stream at the point of contact with the surface becomes laminar. This, consequently, results in a lower velocity of air impacting at the surface and a consequentially lower de-pollution rate.
Moreover, not all the air will actually come in contact with the photocatalytic surfaces, further undermining its efficiency. To ensure a sound operating application, the photocatalytic material needs to be in a position where all the air comes in contact with the treated surface and travels over it in a turbulent air flow. This allows as much of the NOx as possible to be in direct contact with the photocatalytic material.
Therefore, if researchers are able to replicate their laboratory results in the field, this could lead to a reduction of 5 to 10 percent of NOx in the surrounding atmosphere. This represents a significant reduction compared to other approaches to reducing air pollution.
Frustrated With Your Current Surface Protection?
Discover The Path To A Nano-Protection Zen!
Get a glimpse of a cleaner stress-free future with our revolutionary nano-technology based protection products.
In many parts of the world, air pollution remains an endemic problem. A world where every building is using ecofriendly nanocoating materials enabling it to actively decompose pollutants in its surrounding atmosphere would go a long way to significantly reduce our carbon footprint. Innovations in nanotechnology hold out the tantalizing prospect of allowing us to re-shape the future of our built environments ecosystem and actively contribute to improving the quality of our air and our life.