The Nobel Prize in Chemistry, 2007 was awarded to Gerhard Ertl, for his entire work that laid the foundations for modern surface chemistry. He had spent the most part of his life studying reactions on surfaces.
Surface chemistry is a very common phenomenon in the industrial and even everyday processes. From producing nitrogen to the destruction of ozone layer each process has a key step where in a deep understanding of the physical and chemical processes underlying the overall reaction plays a vital role in obtaining a higher yield of the product.
Prof Ertl’s work with the Haber-Bosch process was the highlight of the Nobel prize achievement. The process is used to create ammonia from nitrogen and hydrogen in the presence of iron. Though the discovery of the process spawned Nobel prizes for both Haber(1918) and Bosch(1931), the reaction mechanism was unknown until Ertl’s work. To study the reaction mechanisms Ertl made use of a number of techniques, such as generating idealized iron surfaces, introducing precise amounts of gas at low pressure, using a litany of spectroscopic techniques that probed molecules at the surface, and also studying the reverse reaction of the process using heavy hydrogen as a tracer molecule. Prof Ertl discovered that the splitting of the triple bond in the Nitrogen molecule was the slowest step in the Haber-Bosch process. So, to speed up the production of ammonia, the nitrogen molecule cleavage had to be fastened.
Ertl’s work also included the detailed study of carbon monoxide being converted to carbon dioxide over platinum. This reaction – or the one that doesn’t use platinum- is the one that is used by catalytic converters in cars today to reduce the harmful emissions. The detailed and controlled methodology that Ertl used has given rise to modern surface chemistry and earned him the Nobel Prize.