Fig. 7: The OER mechanism of LiNiO2.
From: Unusual double ligand holes as catalytic active sites in LiNiO2
a Schematic 4-step reaction pathways of MAE, LOV, and MLOV OER mechanisms. Free energy of each OER step of b Li0.5NiO2 and LiNiO2 at URHE = 1.23 V. The estimated thermodynamic overpotentials of each potential-determining step are labelled. c MSCV and faradic CV curves recorded in 18O-enriched 0.1 M KOH electrolyte prepared using H218O (99% 18O), showing the mass ion current (iMS) of 18O2, 16O18O and 16O2 along with the faradaic current (iF) and the applied potential E from the first CV scan. (The inset of c) Comparison of the measured iMS(16O18O) curve and the theoretically expected iMS(16O18O) curve purely from electrolyte oxidation, based on the 16O abundance of 1.18% in the electrolyte (Supplementary Equation S27). d The evolution of measured 18O abundance of evolved oxygen (from total DEMS charge) for 18O-labled LiNiO2 with CV cycles in H216O-based 0.1 M KOH electrolyte. The expected 18O fractions are based on the natural isotope abundance and on the measured value from DEMS experiment of unlabelled LiNiO2 in the 16O-based electrolyte.
