Theory and experiments join forces to characterize the electrocatalytic interface

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 116; no. 16; pp. 7611 - 7613
• Main Authors: Steinmann, Stephan N., Wei, Zi-Yang, Sautet, Philippe
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences 16-04-2019
• Subjects: Catalysis; charge transport; Chemical Sciences; COMMENTARIES; defects; electrical energy storage; electrocatalysis; ENERGY STORAGE; materials and chemistry by design; Mechanical Phenomena; mesoscale science; mesostructured materials; Molecular Dynamics Simulation; or physical chemistry; Physical Phenomena; Physical Sciences; Solvents; Surface Properties; synthesis (novel materials); synthesis (scalable processing); Theoretical and
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.1903412116

Electrocatalysis is gaining impetus as a key technology in fuel cells and for the medium-term energy storage in the context of intermittent, renewable energy sources such as wind and solar power. Furthermore, electrocatalysis promises to convert rather inert molecules such as CO 2 and N 2 into reduced products such as CO and ammonia under relatively mild conditions (1, 2). Harnessing the full power of electrocatal-ysis is, however, hampered by a lack of understanding of the governing physical and chemical processes at the metal-electrolyte interface. In PNAS, Cheng et al. (3) bring key insight to the characterization of reaction intermediates during CO 2 electroreduction via first-principles molecular dynamics modeling. This reaction is timely and has, over the last few years, served as the playground for advanced atomistic modeling of elec-trocatalysis (4-9). The general lack of understanding is due to the inherent complexity of the electrified interface and its characterization. The characterization is difficult since most metal-liquid interfaces are amorphous. Therefore, no long-range ordering can be detected. Experimentally , the characterizations heavily rely on spectroscopy that provides average molecular orientations [infrared (IR) and Raman] or elemental composition and oxidation states (X-ray photoelectron, X-ray absorption near-edge, etc.) (10