Fig. 3: Theoretical analysis of T-IrOx for OER electrocatalysis.
From: Tunnel-structured IrOx unlocks catalytic efficiency in proton exchange membrane water electrolyzers
a The ΔGleaching of K+/H+ exchange in a tunnel iridate with a 2 × 2 tunnel configuration at different pH. b The surface phase diagrams for the (001) surface of 2 × 2 tunnel iridium oxide. c Theoretical activity (ηOER) volcano plot using O* and OH* binding energies (ΔGOH and ΔGO − ΔGOH) as descriptors. Point shapes indicate tunnel types. Box plot of d charge transfer energies (εd-p) and e integrated crystal orbital hamilton populations (−ICOHP) of Ir-O bonds of tunnel walls and mouths in these tunnel iridium oxides. Boxes show interquartile ranges (25th–75th percentiles), whiskers show standard deviations, and medians are marked by center lines. f Bader charge of oxygen in these tunnel iridium oxides. The inset illustrates the nucleophilic attack of H2O on O*. Source data are provided as a Source data file.
