Electrocatalysis

The idea to use electrical current to control various chemical reactions has been very attractive since the time when humankind developed the very first electrical power sources. Initial experiments performed more than 200 years ago, for instance on water splitting to produce gaseous hydrogen and oxygen under ambient conditions, clearly demonstrated the power and promise of this approach. The latter has nowadays evolved into various large-scale industrial processes. Importantly, it will also likely play a key role in the future to secure sustainable energy provision worldwide.

In a simple case, in order to initiate a redox reaction using the above-mentioned approach, we need at least two electronically conducting electrodes and an ionically conducting electrolyte. By applying a certain bias, we can generate new compounds at the surface of the electrodes. However, in spite of the apparent simplicity, the efficiency of the overall process is often determined by the structure and composition of the electrode surface as well as by the nature of the electrolyte components.

Attempts to explain and predict these observable phenomena and relate e.g. the measured overall activity with the status of the electrode / electrolyte interface resulted in the appearance of a new special field of science which is now called “electrocatalysis”.

For example, in order to minimize the energy losses during the water splitting and obtain hydrogen fuel for the future sustainable energy provision schemes, we need to develop two efficient electrocatalysts: for hydrogen and oxygen evolution, as illustrated in the Figure below.

The development of electrocatalysts assumes that at least three key factors determining their performance are optimised: activity, selectivity and stability. Primarily, the most critical issue in the search for new materials is the ability to identify active surfaces efficiently. Our research is focused on identification and detailed characterization of new electrocatalysts relevant for future energy provision and storage. Among them are materials for oxygen reduction, hydrogen and oxygen evolution, methanol oxidation etc.

 

Literature:

S. Xue, R.W. Haid, R.M. Kluge, X. Ding, B. Garlyyev, J. Fichtner, S. Watzele, S. Hou, A.S. Bandarenka. Enhancing the hydrogen evolution reaction activity of platinum electrodes in alkaline media using Ni-Fe clusters // Angewandte Chemie International Edition 59 (2020) 10934-10938

Y. Liang,(1) D. Mclaughlin,(1) C. Csoklich, O. Schneider, A.S. Bandarenka. The nature of active centers catalyzing oxygen electro-reduction at platinum surfaces in alkaline media // Energy & Environmental Science 12 (2019) 351-357

J.H.K. Pfisterer(1), Y. Liang(1), O. Schneider, A.S. Bandarenka. Direct instrumental identification of catalytically active surface sites // Nature 549 (2017) 74–77

J. Tymoczko, F. Calle-Vallejo, W. Schuhmann, A.S. Bandarenka. Making the hydrogen evolution reaction in polymer electrolyte membrane electrolysers even faster // Nature Communications 7 (2016) 10990

F. Calle-Vallejo(1), J. Tymoczko(1), V. Colic, Q.H. Vu, M.D. Pohl, K. Morgenstern, D. Loffreda, P. Sautet, W. Schuhmann, A.S. Bandarenka. Finding optimal surface sites on heterogeneous catalysts by counting nearest neighbors // Science 350 (2015) 185-189.

F. Calle-Vallejo, M.T.M. Koper, A.S. Bandarenka, Tailoring the catalytic activity of electrodes with monolayer amounts of foreign metals // Chemical Society Reviews 42 (2013) 5210-5230.

A.S. Bandarenka, M.T.M. Koper. Structural and electronic effects in heterogeneous electrocatalysis: towards a rational design of electrocatalysts // Journal of Catalysis 308 (2013) 11-24.

A.S. Bandarenka, E. Ventosa, A. Maljusch, J.  Masa, W. Schuhmann, Techniques and methodologies in modern electrocatalysis: evaluation of activity, selectivity and stability of catalytic materials // Analyst 139 (2014) 1274-1291.

 

F. Calle-Vallejo,(1) Jakub Tymoczko,(1) V. Colic, Q.H. Vu, M.D. Pohl, K. Morgenstern, D. Loffreda, P. Sautet, W. Schuhmann, A.S. Bandarenka. Finding optimal surface sites on heterogeneous catalysts by counting nearest neighbors // Science 350 (2015) 185-189.