Theoretical framework developed by University of Tartu researchers creates new opportunities for clean energy production

An international study, involving researchers from the University of Tartu Institute of Chemistry, was recently published in Chemical Society Reviews. It provides the most comprehensive theoretical description to date of electrocatalysis and how its current limitations can be addressed. The research establishes a framework that helps design more efficient fuel cells, electrolysers, and other clean energy conversion devices. 

Electrocatalysis is a process that enables to convert electrical energy into chemical energy and vice versa – for example, in hydrogen production or in fuel cells.  

More specifically, the article explains so-called scaling relations. One of the authors of this study, Nadežda Kongi, Associate Professor in Colloidal and Environmental Chemistry at the University of Tartu, explained that these are the laws of nature that link the strengths of different reaction steps and determine how good a catalyst can ultimately be. A catalyst is a substance that accelerates chemical reactions without being consumed in the process. In electrocatalysis, it allows energy to be converted much more efficiently and with lower energy consumption. 

The scaling relations have so far set limits to the efficiency of catalysts. “It means that when one reaction step is improved, another deteriorates. This, in turn, sets boundaries on how efficient the catalyst can be,” Kongi said. She explained that if it were possible to overcome scaling relations, hydrogen production, fuel cells, and battery performance could be made more efficient. This would be a major achievement in the energy sector, as these technologies play a key role in the green transition.  

Five options to outsmart scaling relations 

The authors of the article have created a theoretical framework for scientists, which integrates chemistry, energy, and geometry into a unified system. They define five general strategies that can be used to manipulate scaling relations in electrocatalysis: tuning, breaking, switching, pushing, and bypassing.  

As an important new observation, Kongi pointed out that the geometry of the catalyst, for example, the arrangement of atoms, plays a significantly greater role than previously thought. “The distance between atoms on the catalyst’s surface determines both the rate and the pathway of the reaction,” Kongi said. 

Two decades of knowledge combined into one 

According to Nadežda Kongi, this research joins the theoretical and experimental understanding of the last twenty years into a single whole. “Our work provides a direction for developing a new generation of catalysts, which are crucial for creating clean energy solutions. The result is a practically applicable theory that guides the development of next-generation clean energy technologies.” 

The article “Twenty years after: scaling relations in oxygen electrocatalysis and beyond” was published in Chemical Society Reviews, a top-tier journal of chemical sciences.  The authors of the article from the University of Tartu are Nadežda Kongi, Associate Professor in Colloidal and Environmental Chemistry, and Vladislav Ivaništšev, Associate Professor in Physical and Electrochemistry. 

https://pubs.rsc.org/en/content/articlehtml/2025/cs/d5cs00597c