Revision 1

Accepted · first revision · record

Title: Why hydrogen evolution on platinum slows down in alkaline solution
Plain: Platinum makes hydrogen from water roughly a hundred times more slowly in basic solution than in acid. The reason for this slowdown is still disputed.
Precise: Explain the drop of the exchange current density of the hydrogen evolution and oxidation reactions on Pt from pH 0 to pH 13 (about two orders of magnitude), distinguishing between hydrogen binding energy shifts, the interfacial water reorganization and the potential of zero free charge, and cation-hydroxyl interactions. An answer is a model that predicts the measured rate versus pH and versus cation identity.
Settled by: pH- and cation-resolved kinetics on single-crystal Pt with in situ spectroscopy, matched by constant-potential simulations of the proton or water discharge step.
Kind: phenomenon
Answer type: mechanism
References: (empty)
Literature status: contested
Status note: (empty)
Posed since: (empty)