Amazing stuff!
"... The problem is that the half-reaction that produces oxygen, known as the oxygen evolution reaction (OER), is difficult and inefficient and takes more energy than predicted by theory. “It should require 1.23 V,” ... “but in reality, it requires more like 1.5 or 1.8 V.” This extra energy cost is one of the reasons why water splitting has not been implemented on a large scale ...
The team’s findings, ... suggest that controlling the orientation of water at the interface with the electrode could improve OER catalyst performance. For example, surfaces engineered to pre-align water molecules might lower the kinetic barriers to water splitting. “The results could also refine electrochemical models by incorporating structural water energetics,” ... “And beyond the OER, water alignment may also influence other reactions such as the hydrogen evolution reaction and CO₂ reduction to liquid fuels, potentially impacting multiple energy-related technologies.” ..."
From the abstract:
"While water’s oxygen is the electron source in the industrially important oxygen evolution reaction, the strong absorber problem clouds our view of how the Stern layer water molecules orient themselves in response to applied potentials.
Here, we report nonlinear optical measurements on nickel electrodes held at pH 13 indicating a disorder-to-order transition in the Stern layer water molecules before the onset of Faradaic current.
A full water monolayer (1.1 × 1015 centimeter−2) aligns with oxygen atoms pointing toward the electrode at +0.8 volt and the associated work is 80 kilojoule per mole. Our experiments identify water flipping energetics as a target for understanding overpotentials, advance molecular electrochemistry, provide benchmarks for electrical double layer models, and serve as a diagnostic tool for understanding electrocatalysis."
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