Deres Majestæt, Hr Minister, Professor Jens Kehlet Nørskov.
Dear colleagues, Ladies and Gentlemen.
It is a great pleasure and an honor for me to motivate the choice of Professor Jens Kehlet Nørskov as recipient of the Niels Bohr International Gold Medal 2018.
Niels Bohrs model of the constitution of atoms and molecules is taught in physics classes in schools in the whole world, and it paved the way towards the formulation of quantum mechanics. In quantum mechanics, we describe microscopic particles as if they are waves. Waves are complicated objects and the quantum mechanical theory of more than just two interacting particles is very demanding.
Richard Feynman, recipient of the Niels Bohr Medal in 1973, once said: “Nature isn’t classical, dammit, and if you want to make a simulation of nature, you’d better make it quantum mechanical, and by golly it’s a wonderful problem, because it doesn’t look so easy.”
Professor Jens Nørskov has addressed this wonderful problem. Meeting the demands of applications in physics and chemistry, Jens Nørskov has developed theoretical methods that describe the complex organization of matter and the chemical processes that occur at material surfaces.
Niels Bohrs theory and the early quantum mechanics account for the electronic structure of single atoms, but they do not answer questions such as the catching title of an article by Jens Nørskov and Bjørk Hammer: Why gold is the noblest of all the metals. Gold is more shiny than other materials because of the way the surface layer of gold atoms interacts quantum mechanically with other atoms and molecules that approach it. This is, by golly, not an easy problem.
Jens Nørskov’s enquiry into complex physical and chemical processes is motivated by the same kind of curiosity and intellectual drive that motivated Niels Bohr in his research.
On September 1, 1939, the first day of World War II, Niels Bohr published an article with John Wheeler on the energy released in the fission of heavy atomic nuclei. During and after the war, Niels Bohr urged international collaboration to prevent an accelerating nuclear arms race and to promote peaceful and safe application of nuclear power. In 1955, Niels Bohr was awarded the Gold Medal that now carries his name for his research and for his promotion of responsible use of nuclear energy.
In the same way as Niels Bohr addressed pertinent research questions of his time, Jens Nørskovs research addresses the great challenges of our time, and he has led a number of research centers and stimulated collaboration across Denmark, internationally and between Universities and industry.
The study of chemical processes on the surface of gold and other materials is not only an academic exercise. These are the processes, that remove toxic components from the exhaust of our car engines and power plants and they are crucial for the production of a range of products in the chemical industry.
I have a Gold Card issued by Scandinavian Airlines. With this card, I can avoid some of the hassle in the airports and use so-called fast track through security check and boarding of my plane. I am sure Jens Nørskov travels more than I do, and he may well be in possession of the even more attractive Platinum Card with further benefits.
In a similar manner as they smoothen our travel, shiny surfaces of gold and platinum facilitate and provide fast track processes in the microscopic world of atoms. The pathways of chemical processes, from the breaking of initial molecular substances to the formation of the final ones, pass through intermediate states that have higher energy than the final products. That energy must be provided for the processes to occur. But if the processes occur near a surface, new reaction pathways appear where the atoms may ride along the surface at lower intermediate energies on their way to the desired final molecules. The surface serves as a catalyst that facilitates the process (like the Gold and Platinum cards give fast track access in airports).
Finding appropriate surface catalyst materials that lower the energy consumption, even if it is only by a small amount, holds potential to improve industrial processes and to enable mechanisms that can convert greenhouse gases efficiently into new sustainable fuels and other useful chemicals.
Niels Bohr introduced the compound nucleus and liquid drop models to simplify the quantum treatment of nuclear fission and, in a similar manner, Jens Nørskov has developed simple models and rules that embody the main features revealed by large scale computer simulations of the complex quantum dynamics.
It is impossible to systematically test or simulate all possible combinations of materials, and Jens Nørskovs so-called scaling relations and volcano plots have become main tools in the international research in catalyst behavior.
After a career with positions in both Industry and Universities, Jens Nørskov was in 2010 headhunted as professor and founding director of the Center for Interface Science and Catalysis, at Stanford University. With a research grant from the Villum Foundation he was recently recruited back to Denmark, where he will continue his research.
The committee finds that Jens Nørskovs work represents a timely and important extension on Niels Bohrs fundamental understanding of atomic structure and dynamics. Rather than maximizing the atomic energy from nuclear fission, Jens Nørskovs catalysts minimize the energy in atomic and molecular processes. The scientific quality and the perspectives for application of this research make Jens Kehlet Nørskov an excellent choice for the Niels Bohr Medal for 2018.