A Universal Approach to Quantify Overpotential-Dependent Selectivity Trends for the Competing Oxygen Evolution and Peroxide Formation Reactions: A Case Study on Graphene Model Electrodes
journal contributionposted on 2021-05-11, 17:35 authored by Anna Ivanova, Andrew Chesnokov, Dmitry Bocharov, Kai S. Exner
In this article, we study the competing oxygen evolution and hydrogen peroxide (H2O2) formation reactions for periodic models of graphene with different active-site concentrations by means of density functional theory (DFT) calculations. Linking the DFT calculations to ab-initio thermodynamic considerations in conjunction with microkinetic modeling enables gaining deep insights into the activity and selectivity trends of graphene-based electrodes as a function of applied bias. We illustrate that both the coverage of intermediates on the electrode surface and the applied electrode potential have a significant effect on the Faradaic efficiency for the electrocatalytic production of H2O2. The presented approach to study overpotential-dependent selectivity trends allows deriving design criteria for peroxide formation, which may serve as a guideline for further studies to realize selective formation of H2O2 using carbon-based materials.
graphene-based electrodescarbon-based materialselectrode surfacehydrogen peroxideelectrocatalytic productionstudy overpotential-dependent selec...active-site concentrationsUniversal Approachformation reactionsGraphene Model Electrodesmicrokinetic modelingDFT calculationsperoxide formationPeroxide Formation Reactionsdesign criteriaQuantify Overpotential-Dependent Se...oxygen evolutionFaradaic efficiencyselectivity trendsCase StudyH 2 O 2Oxygen Evolution