The role of adsorbates in electrocatalytic systems: An analysis of model systems with single crystals

In Situ Probe of the Hydrogen Oxidation Reaction Intermediates on PtRu a Bimetallic Catalyst Surface by Core–Shell Nanoparticle-Enhanced Raman Spectroscopy

“…Alkaline-anion-exchange membrane fuel cells (AEMFCs) have received ever-growing attention in recent years due to their allowance of the use of catalysts with low or no Pt with longer lifetimes. − However, the kinetics of the hydrogen oxidation reaction (HOR) in alkaline electrolytes is 2–3 orders of magnitude slower than that in acidic electrolytes, which is the main bottleneck that hinders the development of alkaline fuel cells. − Introducing a second metal, such as Ni, , Rh, , Ir, , Ru, − etc. to incorporate with Pt to form bimetallic electrocatalysts with fine structure and composition control − is a promising approach to improve the alkaline HOR activity.…”

“…In alkaline media, the HOR proceeds through a Tafel–Volmer or Heyrovsky–Volmer sequence, which involves H 2 dissociative adsorption onto the active sites (adsorbed hydrogen, H ad ) and the combination of H ad and OH – or adsorbed hydroxyl (OH ad ) to form H 2 O. − The hydrogen binding energy (HBE) theory − , stresses that H ad is the key reaction intermediate of the HOR, and other external factors, such as electrode potential, pH, ions, and so on, affect the HOR kinetics and mechanism by disturbing the HBE. A bifunctional mechanism − emphasizes the cooperative adsorption of both H ad and OH ad onto the active cites.…”

Charge Reorganization at the Adsorbate Covered Electrode Surface Probed through in Situ Resonant X-ray Diffraction Combined with ab Initio Modeling

“…Adsorbates can also affect the electrode stability and result in degradation of the electrode. [6][7][8][9][10] Insights into the exact mechanism of adsorbate bonding at the electrochemical interface, the polarizability of the bond and its dependence on the applied potential will thus help to better understand and design electrochemical processes. In addition, insight into bond formation and modification by surrounding ions or an electrical field is of more general interest to several areas in Chemistry, such as bio-molecular or complex-formation .…”

“…Adsorbates play a crucial role in electrochemical processes such as phase formation during electrodeposition − and during electrocatalytic reactions, where they can be present at the interface either as adsorbed species from the electrolyte solution or as reaction intermediates. Adsorbates can also affect the electrode stability and result in degradation of the electrode. − Insights into the exact mechanism of adsorbate bonding at the electrochemical interface, the polarizability of the bond, and its dependence on the applied potential will thus help to better understand and design electrochemical processes. In addition, insight into bond formation and modification by surrounding ions or an electrical field is of more general interest to several areas in chemistry, such as biomolecular or complex formation. , …”

Enhanced electrochemical hydrogen oxidation reaction and suppressed hydrogen peroxide generation properties on Pt/Ir(111) bimetallic surfaces

“…, making it difficult to distinguish the well-acknowledged factors influencing catalytic properties such as the bifunctional (ensemble) effect, ligand effect, and strain effect. 8–10…”