skip to main content

SciTech ConnectSciTech Connect

Title: Opening gates to oxygen reduction reactions on Cu(111) surface

Electrocatalytic reduction of oxygen is composed of multiple steps, including the diffusion-adsorption-dissociation of molecular oxygen. This study explores the role of electrical double layer in aqueous medium in quantifying the rate of these coupled electrochemical processes at the electrode interface during oxygen reduction. The electronic, energetic, and configurational aspects of molecular oxygen diffusion and adsorption onto Cu(111) in water are identified through density functional theory based computations. The liquid phase on Cu(111) is modeled with hexagonal-ordered water bilayers, at two slightly different structures, with O–H bonds either facing the vacuum or the metal surface. The results indicate that the energetically preferred structure of water bilayers and adsorption configuration of O{sub 2} are different in cathodic and anodic potentials. The diffusion of O{sub 2} is found to be heavily hindered at the water/metal interface because of the ordering of water molecules in bilayers as compared to the bulk liquid. The unique correlations of diffusion and adsorption kinetics with water structure identified in this work can provide clues for improving oxygen reduction efficiency.
Authors:
;  [1]
  1. Illinois Applied Research Institute, University of Illinois at Urbana-Champaign, Champaign, Illinois 61820 (United States)
Publication Date:
OSTI Identifier:
22415577
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 142; Journal Issue: 12; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ADSORPTION; CHEMICAL REACTION KINETICS; COMPARATIVE EVALUATIONS; COPPER; CORRELATIONS; DENSITY FUNCTIONAL METHOD; DIFFUSION; DISSOCIATION; ELECTROCHEMISTRY; ELECTRODES; INTERFACES; LAYERS; LIQUIDS; MOLECULES; OXYGEN; POTENTIALS; REDUCTION; SURFACES; WATER