Revamped Electrode Models for Driving Electrochemical Reactions under Alkaline Conditions

Driving electrochemical reaction with bias in 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 running electrochemical reactions under alkaline conditions. Through an overhaul of the computational hydrogen electrode (CHE), we show that hydroxide ions do adsorb on many late transition metals even under negative bias. This is even so 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 for how to model electroreduction reactions under alkaline conditions.