Role of water structure in alkaline water electrolysis

Role of water structure in alkaline water electrolysis

Blog Article

Summary: Herein, with the help of experimental and first-principles density functional theory (DFT)-based studies, we have shown that structural changes in the water coordination in electrolytes having high alkalinity can be a possible reason for the reduced catalytic activity of platinum (Pt) in high pH.Studies with polycrystalline Pt electrodes indicate that electrocatalytic HER activity reduces in terms of high 7-OH overpotential required, high Tafel slope, and high charge transfer resistances in concentrated aqueous alkaline electrolytes (say 6 M KOH) in comparison to that in low alkaline electrolytes (say 0.1 M KOH), irrespective of the counter cations (Na+, K+, or Rb+) present.The changes in the water structure of bulk electrolytes as well as that in electrode-electrolyte interface are studied.

The results are compared with DFT-based analysis, Wooden Kit and the study can pave new directions in studying the HER process in terms of the water structure near the electrode-electrolyte interface.