Electrolyte Anions Suppress Hydrogen Generation in Electrochemical CO Reduction on Cu.

ABSTRACT: In this study, we employed electrochemical-mass spectrometry (EC-MS) to elucidate the role of halide anions in electrochemical CO₂ and CO reduction. We found that the undesired hydrogen evolution reaction (HER) was significantly suppressed by the anion used. Specifically, the rates of H₂ production decreased in the order KF > KCl > KI, meaning that I^- most strongly suppressed HER. Interestingly, CO reduction products showed an inverse relationship to HER, with KI leading to the highest rate of CO reduction. By pairing our experimental findings with classical molecular dynamics simulations, we propose a mechanism wherein halide anions influence the dynamic interplay between CO reduction and HER by modulating the competition of H* and CO* for active sites on

SUBMITTER: Fuller L 

PROVIDER: S-EPMC11878348 | biostudies-literature | 2025 Mar

REPOSITORIES: biostudies-literature