Publication date: 28th August 2024
Electrocatalysis at the electrode-electrolyte interface is fundamentally governed by electron transfer across the electric double layer (EDL), highlighting a crucial mechanistic link between electrocatalytic properties and EDL structure. A central question in this field is the role of alkali metal cations at this interface, commonly known as the “cation effect”. This presentation will outline our ongoing research aimed at uncovering the fundamental principles underlying the cation effect in several important electrochemical reactions in aqueous environments. Using advanced in situ analytical techniques, we have discovered that alkali metal cations are not merely spectators, as traditionally believed, but actively influence the kinetics and mass transport in electrocatalysis. The identity and concentration of the alkali metal cation are critical in modulating electrocatalytic activity and selectivity, as well as affecting electrode stability. We will present a mechanism of cation-coupled electron transfer and its potential role in alkaline hydrogen evolution reactions. By gaining a deeper understanding of how alkali metal cations affect electrocatalysis, we aim to propose a novel conceptual framework for improving electrocatalytic processes.