Revamped Electrode Models for Driving Electrochemical Reactions under Alkaline Conditions

Driving
electrochemical reactions with a bias in an aqueous
environment
is an attractive approach for sustainable chemical synthesis, but
understanding reaction dynamics remains a serious challenge in electrocatalysis.
Computational techniques and concepts are necessary to elucidate the
underpinnings of creating catalytic sites that are highly active,
selective, and stable. Herein, we elucidate the intrusive role of
hydroxide ions in the running of electrochemical reactions under alkaline
conditions. Through an overhaul of the computational hydrogen electrode
(CHE) model, we show that hydroxide ions can adsorb on many late transition
metals, even on metals like Cu and Pt, where the OH* binding energy
is energetically uphill relative to H2O (l). We provide
a computational framework for modeling reaction energetics with OH–* relative to OH–(aq), using HER
and CO2R as examples of how to model electroreduction reactions
under alkaline conditions.