____________________Dataset for Gelatine-assisted Defect Engineering in LaCoO3 and its Impact on Oxygen Electrocatalysis article____________________ Last updated: 2024-12-11 ______Contact______ * Petr Krtil * ORCID: 0000-0001-8447-1333 * J. Heyrovsky Institute of Physical Chemistry, Czech Academy of Sciences * Dolejskova 3, 182 23, Prague 8, Czech Republic ______Principal Investigator______ * Karel Bouzek * ORCID: 0000-0002-0394-0634 * Dept. of Inorganic Technology, Faculty of Chemical Technology, University of Chemistry and Technology, Prague * Technicka 5, 166 28, Prague 6, Czech Republic ______Data manager or custodian______ * Šárka Paušová * ORCID: 0000-0003-2494-1510 * Dept. of Inorganic Technology, Faculty of Chemical Technology, University of Chemistry and Technology, Prague * Technicka 5, 166 28, Prague 6, Czech Republic ______License______ *Dataset for "Dataset for Gelatine-assisted Defect Engineering in LaCoO3 and its Impact on Oxygen Electrocatalysis article" © 2024 by Petr Krtil is licensed under CC BY *lisense information: https://creativecommons.org/licenses/by/4.0/ ------------------------------------------------------------------------------------------------ ______About the dataset______ Nanocrystalline LaCoO3 materials prepared by spray-freeze freeze-drying approach in the presence of various amounts of gelatin were tested in oxygen electrocatalysis in alkaline media. The presence of gelatin in the reaction mixture affects the distribution of the oxygen vacancies as well as formation of Ruddlesen–Popper (RP) defects within nanocrystals. The materials prepared at low gelatin concentration (c  1.5g/L) tend to locate the oxygen vacancies at the domain boundaries while increasing gelatin concentration promotes a larger formation of superstructures when the oxygen vacancies get ordered along the {100] pseudocubic direction in the crystal. The ordered vacancies as well RP faults are primary sites of exfoliation in acid media steering the electrocatalytic behavior of the prepared materials in both oxygen evolution and oxygen reduction. The exfoliation significantly promotes the OER activity via a new surface formation increasing the presence of Co (III) - Co (IV) species at the surface which are responsible for oxygen evolution. The exfoliation, on the other hand, leads to a change of the ORR mechanism promoting four-electron reduction over the two-electron peroxide formation. This behavior can be attributed to a change of reactivity of the exfoliated surfaces which apparently adsorb peroxo intermediates more strongly than as prepared materials. ______Methods of data collection______ * Sample preparation All samples were by spray freeze freeze drying approach from solution based precursors in presence of variable amount of gelatin. Prepared amorphous precursors were annealed at 400 C in air and finally treated by diluted acid to enhance electrochemical activity. Smaple assignment: Sample 1 LaCoO3 prepared without gelatin Sample 2 LaCoO3 prepared with 0.3 g/L of gelatin Sample 3 LaCoO3 prepared with 0.8 g/L of gelatin Sample 4 LaCoO3 prepared with 1.5 g/L of gelatin Sample 5 LaCoO3 prepared with 2.5 g/L of gelatin Sample 6 LaCoO3 prepared with 5.0 g/L of gelatin Sample 7 LaCoO3 prepared with 7.5 g/L of gelatin * XRD data All materials were characterized by powder X-ray diffraction using Rigaku Miniflex 600 powder X-ray diffractometer with Cu Kα radiation operating at 30 kV and 10 mA. Acquisition time was 3 s per point. * Electrochemical data Electrochemical data were generated in voltammetry experiments in 0.1 M KOH in a single compartment three-electrode cell with a rotating disk electrode (RDE) set-up controlled by an Autolab PGSTAT30 potentiostat. A 5 mm glassy carbon electrode was utilized as a working electrode coated with a thin film of catalyst ink. Pt mesh and saturated calomel electrode (SCE) were used as counter and reference electrodes, respectively. The electrolyte was purged with argon (Ar; Messer, > 99.9 %,) gas for 30 minutes before measurements. Voltammetry was performed in the potential range of -0.5 V to 1.7 V vs RHE at a scan rate of 10 mV s-1. Linear scan voltammetry (LSV) was done in the potential range from 1.0 V–1.7 V vs RHE at a scan rate of 5 mV s-1. Tafel slopes were derived from linear scan voltammetry curves recorded in the potential range of 1.1 V-1.8 V at a scan rate of 1 mV s-1. Electrochemical Impedance Spectroscopy (EIS) measurements were performed in a frequency range from 15 kHz to 1 kHz with an amplitude of 10 mV (peak to peak) to determine the uncompensated resistance of the system. ______Methods of data processing______ All measured potentials were recalculated from SCE to RHE scale by adding 1.009 V. ------------------------------------------------------------------------------------------------ ______File formats______ * Voltammetric data - tab separated CSV * HRTEM dada – tiff files * Text documents - converted from DOCX to PDF/A * SEM data - tiff files * Diffraction data – tab separated CSV ______Date formats______ * YYYY-MM-DD * HH-MM-SS 24hr formate ______Units and abbreviations______ * All voltammetric curves are current (A) vs potential (V) * All Diffraction patterns are in the measured intensity (a.u.), background intensity (a.u.) and difference (a.u.) vs. diffraction angle (deg) ------------------------------------------------------------------------------------------------ ______List of files______ * Diffractograms of sample 1 VZ2_022_021_UFCH_D_0001_v1.csv * Diffractograms of samples 2-8 VZ2_022_021_UFCH_D_0002_v1.csv * Particle size distribution of samples 1-8 VZ2_022_021_UFCH_D_0003_v1.csv * HRTEM images of the prepared materials VZ2_022_021_UFCH_D_0004_v1.tiff * SEM images of the prepared materials VZ2_022_021_UFCH_D_0005_v1.tiff * Cyclic voltammetry on the Samples 1 and 7 as prepared and exfoliated VZ2_022_021_UFCH_D_0006_v1.csv * Linear scan voltammetry on the Samples 1 - 7 as prepared and exfoliated VZ2_022_021_UFCH_D_0007_v1.csv * RRDE recorded ORR disk currents of Samples 1, 4 and 7 as prepared and exfoliated VZ2_022_021_UFCH_D_0008_v1.csv * RRDE recorded ORR ring currents of Samples 1, 4 and 7 as prepared and exfoliated VZ2_022_021_UFCH_D_0009_v1.csv * RRDE base n values for ORR of Samples 1, 4 and 7 as prepared and exfoliated VZ2_022_021_UFCH_D_0010_v1.csv * Voltammetric data of Samples 1, 4 and 7 as prepared and exfoliated VZ2_022_021_UFCH_D_0011_v1.csv