So what’s the point in getting so tiny?

Did you know that one nanoparticle is 10,000 times thinner than one human hair? Since the 90’s, chemists have made significant progress in managing increasingly tinier particles. Thierry Lemercier, Solvay Research and Innovation (R&I) Fellow, recently presented at a congress in Paris a comprehensive paper about nanostructured materials making the link with our activities in the field.

A lot of nanoparticles can be found in nature in various forms, from the volcanic smoke to the woodfire or to even more complex nanostructures such as the wings of blue butterflies or the leaves of water lilies. Today, the classical definition of a “nano” refers to a particle that is a size ranging from 1 to 100 nanometers (nm), so 1,000 times thinner than a human cell and 10,000 times thinner than your hair.

Scientists have understood that a size reduction of the 100nm particle can have a huge impact on inorganic materials’ properties. It’s particularly true for the surface reactivity and for the change in the optical properties. Imagine that, in 100gr of 5nm alumina powder, the total useful surface is equivalent to three soccer playgrounds. It’s huge, isn’t it? That’s why nanoparticles can be used as catalysts.

A typical example that illustrates the use of nanomaterials in optical application is the use of TiO2 as photocatalyst agents in self-cleaning glass and quantum dots (Qdots). Qdots are interesting very thin nanoparticles showing emission colors varying from blue to red when the size increases from 2nm to 7nm. It’s amazing to think that chemists are now able to industrially control the nanomaterials’ size and emission color with a high degree of precision.

Thierry Le Mercier, Solvay R&I Fellow, is an expert in Functional Inorganic Materials. He recently presented at a congress dedicated to Nanomaterials in Paris a comprehensive paper about nanostructured materials. During his presentation, he explained the feasibility to define their size and surface area, their shape, and the chemistry of the surface at the industrial scale.

Indeed, We are an important actor (producing and/or handling around 1 Mio tons/year — 2016 figure) in the “nano” world with a wide range of materials with a variety of size and shape that seems almost unlimited. It produces tailor-made nanostructured materials such as: amorphous silica for tires, cerium mixed oxides, etc.

We have been developing highly dispersible silica for tire reinforcement. Elementary nanoparticles are assembled in morphologically controlled aggregates and then in agglomerates. In order to be easily incorporated in the rubber by the customer, silica is shaped in a micro pearl which has exceptional flow ability. By mixing with the rubber, micro pearls break, delivering aggregates which are then linked to the rubber. Tires’ properties are then enhanced (decrease of consumption of fuel, increase safety on wet road, durability of tires).

Depending on its architecture and size, Cerium oxide (CeO2) can play different roles: it can be used as an oxygen buffer in automotive catalysts, as a polishing agent, as a UV filter, etc. — So many talents in one personality!

We have differentiating position in manufacturing mixed oxides of zirconium, cerium and other rare earths, that bring superior performances in your gasoline car exhaust system. The oxides provide a high thermal stability (high surface area is kept even at temperature higher than 900°C), and excellent oxygen storage capacity, which is fundamental in the catalytic process of conversion of pollutants by the TWC process (three way catalysis: simultaneous conversion of NOx, CO and hydrocarbons into N2, CO2 and water).

Would you know more about nano? Don’t hesitate to do the training and get in touch with the Paracelse group of expert colleagues.