Platinum, an expensive noble metal, is an important component of catalytic convertors in cars. The less of it you need, the cheaper your catalytic convertor is to produce. The company Delft Intensified Materials Production (Delft IMP) uses a technology that can deposit materials atomic layer by atomic layer to produce the same quality catalyst for catalytic convertors with 35 percent less platinum.
‘Our technology can indeed be used to very accurately and energy-efficiently produce catalysts in powder form for use in car exhausts,’ says CEO Bart van Limpt of the fledgling company that is a spin-off of Delft University of Technology. ‘Platinum lies at the heart of these catalysts. With our method, we can very accurately apply thin layers of platinum to grains of a cheap carrier material. This approach requires 35 percent less platinum than the current processes. As the production cost of a catalyst is largely determined by the cost of the platinum, our approach can considerably reduce the price of catalysts.’
The same technique can also be used in a wide range of other applications. One example is coating lithium-ion battery particles with aluminium oxide to ensure that the battery particles degrade less quickly; this increases the lifespan of such a battery. Another example is covering pigments with a thin transparent protective layer so that they do not lose their colour under the influence of sunlight or water.
Van Limpt attends congresses with a simple model that he uses to demonstrate how the technology works. Small spherical particles in a glass tray are brought into motion using nitrogen gas. The individual spheres can be uniformly coated by allowing the coating in gaseous form to pass through the glass tray. ‘We use a specific chemistry that ensures you always get the same final product. This works better than the wet chemistry often used at present, in which various substances are mixed together in their liquid phase and you are left hoping that the same chemical reaction occurs throughout the entire mixture.’
The technology is based on a technique called atomic layer deposition (ALD). This technique is already used widely in the semiconductor industry to very accurately apply various materials layer-by-layer to silicon wafers. ‘We are now introducing this technology to the process industry for the first time,’ says Van Limpt. The fledgling company has already received a Valorisation Grant from NanoNextNL and a Take-Off Grant from STW, and it also reached the top-10 of the European ClimateLaunchpad, a competition for highly promising cleantech start-ups.
The process has emerged from the academic research performed by Ruud van Ommen of Delft University of Technology. He developed and patented a way of scaling up the ALD process, which can normally coat several grams of material per hour at the lab scale, into a fully-fledged production facility that can coat kilograms per hour. ‘With the help of the Valorisation Grant, we will construct this pilot-scale system to show potential clients the strength of the technology,’ says Van Limpt.
The entrepreneur is a convincing promoter of his product’s many benefits. ‘Catalysts are often made using expensive components. With our technology, we can obtain the same efficacy with a far smaller quantity of the expensive material. Furthermore, this technology does not require high temperatures and produces very few undesired by-products. This means that besides reducing costs, our technology is also far more environmentally friendly than the current production methods. This technology can be used nearly universally. As soon as our pilot-scale reactor has been built, we will show a wide range of manufacturers what our technology could mean for their company by using our reactor to produce their specific product according to their specific requirements.’