Electrochemical surface science twenty years later: Expeditions into the electrocatalysis of reactions at the core of artificial photosynthesis

• Published in: Surface science 2015-01, Vol.631 (C), p.285-294
• Main Authors: Soriaga, Manuel P., Baricuatro, Jack H., Cummins, Kyle D., Kim, Youn-Geun, Saadi, Fadl H., Sun, Guofeng, McCrory, Charles C.L., McKone, James R., Velazquez, Jesus M., Ferrer, Ivonne M., Carim, Azhar I., Javier, Alnald, Chmielowiec, Brian, Lacy, David C., Gregoire, John M., Sanabria-Chinchilla, Jean, Amashukeli, Xenia, Royea, William J., Brunschwig, Bruce S., Hemminger, John C., Lewis, Nathan S., Stickney, John L.
• Format: Article
• Language: English
• Subjects: Alloys; Artificial photosynthesis; Carbon dioxide reduction reaction; Electrocatalysis; Electrochemistry-surface science apparatus; Electroctrochemical surface science; Expeditions; Fuel cells; Noble metals; Photosynthesis; Reduction; Single crystals; Transformations; Water-splitting reaction
• ISSN: 0039-6028; 1879-2758
• DOI: 10.1016/j.susc.2014.06.028

Surface science research fixated on phenomena and processes that transpire at the electrode-electrolyte interface has been pursued in the past. A considerable proportion of the earlier work was on materials and reactions pertinent to the operation of small-molecule fuel cells. The experimental approach integrated a handful of surface-sensitive physical–analytical methods with traditional electrochemical techniques, all harbored in a single environment-controlled electrochemistry-surface science apparatus (EC-SSA); the catalyst samples were typically precious noble metals constituted of well-defined single-crystal surfaces. More recently, attention has been diverted from fuel-to-energy generation to its converse, (solar) energy-to-fuel transformation; e.g., instead of water synthesis (from hydrogen and oxygen) in fuel cells, water decomposition (to hydrogen and oxygen) in artificial photosynthesis. The rigorous surface-science protocols remain unchanged but the experimental capabilities have been expanded by the addition of several characterization techniques, either as EC-SSA components or as stand-alone instruments. The present manuscript describes results selected from on-going studies of earth-abundant electrocatalysts for the reactions that underpin artificial photosynthesis: nickel-molybdenum alloys for the hydrogen evolution reaction, calcium birnessite as a heterogeneous analogue for the oxygen-evolving complex in natural photosynthesis, and single-crystalline copper in relation to the carbon dioxide reduction reaction. •Surface studies of earth-abundant electrocatalysts for artificial photosynthesis•Integrated electrochemistry-surface science apparatus•Surface electrochemical studies of Ni–Mo composites as HER catalysts•Birnessite as heterogeneous analogue of oxygen-evolving complex of Photosystem II•Electrochemically reordered Cu(hkl) from air-oxidized surfaces