Breakthrough in hydrogen research | ScienceDaily

Hydrogen, the lightest of all elements, is in high demand due to its promising role as a sustainable resource in the energy transition. A team from the University of Leipzig and TU Dresden, as part of the hydrogen isotope research training group 1,2,3H, has made a major breakthrough in the efficient and cost-effective supply of isotopes. These are the three forms in which hydrogen occurs in nature: protium, deuterium or tritium. The international team of researchers has taken a big step towards realizing their dream of separating hydrogen isotopes at room temperature and at low cost. The team’s results have now been published in the journal Chemical sciences.

Protium, or hydrogen-1, is the most common form of hydrogen. Deuterium, called heavy hydrogen, is playing an increasingly important role, for example in the development of more stable and effective drugs. A mixture of deuterium and tritium, “superheavy” hydrogen, is used as fuel for nuclear fusion, a sustainable energy source of the future. One of the unsolved problems in hydrogen research is how to provide these isotopes in a very pure form efficiently and cost-effectively, since they have very similar physical properties. Current processes for separating isotopes are not very efficient and consume enormous amounts of energy.

“It has been known for almost 15 years that porous metal-organic frameworks can in principle be used to purify and separate hydrogen isotopes. However, this is only possible at very low temperatures, around minus 200 degrees Celsius, conditions that are very expensive to implement on an industrial scale,” explains Professor Knut Asmis from the Wilhelm Ostwald Institute for Physical and Theoretical Chemistry at the University of Leipzig and spokesperson for the research training group. He adds that the separation mechanism is based on the strongly promoted adsorption of one of the isotopes present on one of the free metal centres of the porous solid. Adsorption is a process by which atoms, ions or molecules of a gas or liquid adhere to a solid, often porous, surface.

Doctoral researchers from the ^1,2,3Elvira Dongmo, Shabnam Haque and Florian Kreuter, all three members of one of the research groups led by Professor Thomas Heine (TU Dresden), Professor Knut Asmis and Professor Ralf Tonner-Zech (both from the University of Leipzig), have now gained a better understanding of the influence of the structure environment on the binding selectivity. This means the question of why one of the isotopes is more likely to stick than the other. This was deciphered in detail in the current study thanks to a synergistic interplay between state-of-the-art spectroscopy, quantum chemical calculations and chemical bond analysis on a model system. “For the first time, we were able to show the influence of the individual atoms of the structure compounds on the adsorption. We can now optimize them in a targeted manner in order to obtain materials with high selectivity at room temperature,” explains Heine.

THE ^1,2,3The research training group H, funded by the German Research Foundation (DFG) with 5.4 million euros over 4.5 years, has been training more than 20 doctoral students since October 2021. It combines the expertise of the University of Leipzig, TU Dresden, the Helmholtz-Zentrum Dresden-Rossendorf and the Leibniz Institute for Surface Engineering to develop new materials, more effective drugs and more sensitive detection methods by bundling funding for basic research and training in the field of hydrogen isotopes. The second cohort of around 15 to 20 doctoral students will start their structured three-year doctoral programme on 1 October 2024.