With the title ” Operando visualization of the hydrogen evolution reaction with atomic scale precision at different metal-graphene interfaces “, the research coordinated by Stefano Agnoli of the Department of Chemical Sciences of the University of Padua was published in the journal “Nature Catalysis” in which, through an extremely sophisticated instrumentation (Electrochemical Scanning Tunneling Microscopy, EC-STM) developed in Padua in collaboration with the electrochemistry group of the same Department, the single catalytic sites were seen with atomic resolution during the electrochemical process of hydrogen production.
“The present study made it possible to identify with atomic precision the presence of catalytic sites and to directly assess their capacity to produce hydrogen in situ . This truly unique combination of spatial resolution and quantification of electrocatalytic activity – says Stefano Agnoli – makes it possible to establish in an extremely accurate way the relationships that link the structure of matter to chemical reactivity and therefore provides the information necessary to build very high catalysts atom after atom. efficiency”.
The EC-STM method has been applied to innovative catalytic systems based on two-dimensional materials based on graphene and non-noble metals, which represent an alternative way to the standard materials currently used for the electrochemical decomposition of water requiring the use of noble metals of high cost and low availability. The quality of the data obtained is unprecedented and has been interpreted through state-of-the-art quantum-mechanical simulation methods developed at the University of Milan Bicocca.
The scenario currently most accredited for a development based on renewable energy sources is the one that is indicated under the name of hydrogen economy . For this ambitious goal to be achieved, the solution goes through a sustainable production of hydrogen from water through a low-cost electrochemical process. This hydrogen is usually called green hydrogen due to the low environmental impact and the virtually infinite availability of the raw material if it were possible to use the water of the oceans.
However, all this requires an optimization of the catalysts essential to make the electrochemical process economical and efficient. Currently the researchers of the field are studying a rational path that allows the optimization of the catalytic materials suitable to achieve this goal.
The Surface Science and Catalysis Group (SSCG) of the Department of Chemical Sciences (DiSC) of the University of Padua directed by Gaetano Granozzi, in collaboration with the theoretical group of the University of Milan Bicocca directed by Cristiana Di Valentin, has achieved an extraordinary result which will have a strong impact for future developments in the field of hydrogen production.