emiliana fabbri et al. (2017), Dynamic surface self-reconstruction is the key of highly active perovskite nano-electrocatalysts for water splitting, in Nature Materials
, 16, 925-931.
Fabbri Emiliana, Nachtegaal Maarten, Binninger Tobias, Cheng Xi, Kim Bae-Jung, Durst Julien, Bozza Francesco, Graule Thomas, SchÃ¤ublin Robin, Wiles Luke, Pertoso Morgan, Danilovic Nemanja, Ayers Katherine E., Schmidt Thomas J. (2017), Dynamic surface self-reconstruction is the key of highly active perovskite nano-electrocatalysts for water splitting, in Nature Materials
Cheng Xi., Fabbri Emiliana et al. (2017), Effect of Ball Milling on the Electrocatalytic Activity of Ba0.5Sr0.5Co0.8Fe0.2O3 towards the Oxygen Evolution Reaction, in Journal of Materials Chemistry A
, 5, 13130.
Fabbri Emiliana (2017), Operando X-ray absorption spectroscopy: A powerful tool toward water splitting catalyst development,, in Current Opinion in Electrochemistry
Kim B. Fabbri E. et al. (2017), Unravelling Thermodynamics, Stability, and Oxygen Evolution Activity of Strontium Ruthenium Perovskite Oxide,, in ACS Catalysis
The growing needs to store large amounts of energy produced from renewable sources have recently targeted substantial R&D efforts towards water electrolysis technologies. The oxygen evolution reaction (OER) occurring at the electrolyzer anode is central to the development of a clean, reliable and emissions-free hydrogen economy since this reaction is hampered by slow kinetics and significant overpotential losses. The development of robust and highly active anode materials for the OER is therefore a great challenge and it has been the focus of much research attention. Towards this end, significant efforts have been directed to the study of the OER activity and stability of several candidate materials. Among these, perovskites have finally emerged as a promising electrocatalysts for the OER. In addition, perovskites show a very desirable design feature in that their electronic properties can be varied in a controlled fashion by substituting in the ABO3 structure the A and B cations, allowing a wide range of compositions to be explored. Such substitutions lead to modifications of the perovskite band structure which in turn might directly affect their catalytic properties. Perovskites’ energy bands are very distinctive and they can be regarded as arising solely from the B site cations. The B cation is most commonly a transition metal, providing the key d-band electrons, and recent works have proposed that perovskite OER electrocatalytic activity depends on the B site electronic configuration. However, no investigations have so far reported on how the perovskite electronic and geometric structure changes during the OER (notably, as a function of electrochemical potentials) or on how it can correlate with the reaction barriers, kinetics, and overpotential. Furthermore, it has recently emerged that the surface compositions of perovskite catalysts can significantly differ from the bulk composition due to surface segregation of various elements. These findings point towards the paramount necessity to deeply study the surface properties of the perovskite catalysts before and after the oxygen evolution reaction, which might cause a further change in the surface composition.The main goal of the present project is to provide a fundamental understanding of OER mechanism and of the design principles governing the OER of highly active perovskite catalysts. This could represent an important breakthrough in the development of efficient energy storage devices. Compared to the state-of-the-art, the novelty of the present study lies in the emphasis pointed towards the fundamental importance of understanding the material electronic structure in operando conditions. This can be achieved through times resolved X-ray absorption spectroscopy (TR-XAS) measurements, which will provide snapshots of the electronic states under operational conditions. Furthermore, we want to investigate how the surface properties of the most promising perovskites catalysts differ from the bulk ones and how they are modified after operative conditions in the OER regime by X-ray photoelectron spectroscopy (XPS).Finally this research project wants to explore the OER catalytic activity of perovskite catalysts beyond the standard alkaline electrolyzer applications (i.e., in neutral electrolyte solution). Indeed, we want to explore the potential applicability of perovskite catalyst for water-oxidation at the anode side coupled with CO2 reduction at the cathode side in CO2-electrolyzers or (or also known as co-electrolyzers). This work will be performed establishing a strong collaboration with Swiss Competence Center for Energy Research (SCCER) directed by Prof Thomas Schmidt at Paul Scherrer Institut, which is currently financing a research project aiming to the development of cathode materials for co-electrolyzers. The preliminary data acquired during the present project might open new prospective for additional funding for a future project based on co-electrolyzer development.