BUSCADOR RECOLECTA

Digital.CSIC. Repositorio Institucional del CSIC

oai:digital.csic.es:10261/336104

30 pages. -- PDF includes: Characterization. -- Density functional theory (DFT) calculations. -- Computational property description. -- Fig. S1. EDS composition of the ternary alloys: FeCoNi, MnFeNi, MnCoNi, and MnFeCo. -- Fig. S2. XRD pattern of the ternary alloys: FeCoNi, MnFeNi, MnCoNi, and MnFeCo. -- Fig. S3. (a) ICP-OES composition, (b) XRD pattern, (c) TEM image, and (d) HRTEM images of a MnFeCoNi quaternary alloy. -- Fig. S4. (a) ICP-OES composition, (b) XRD pattern, (c) TEM image and EDS chemical composition maps, and (d) HRTEM images of a CuMnFeCoNi HEA. -- Fig. S5. Slices of electron density difference of CrMnFeCoNi in (a) side view, (b) front view, and (c) top view. The contour around the atoms represents electron accumulation (red) or electron depletion (blue). -- Fig. S6. Slices of electron density difference of CuMnFeCoNi in (a) side view, (b) front view, and (c) top view. The contour around the atoms represents electron accumulation (red) or electron depletion (blue). -- Fig. S7. OER performance of the ternary alloys. (a) LSV curves, (b) corresponding overpotential at 10 mA/cm2, (c) corresponding Tafel plots, and (d) EIS spectra. -- Fig. S8. (a-g) CV curves with different scan rates of different HEA, quaternary alloy, and ternary alloys in 1.0 M KOH showing the double layer capacitance without electrochemical reactions. (h) Current density at 0.961V vs. RHE plotted against the scan rate and fitted to a linear region to estimate the capacitance. -- Fig. S9. ICP-OES composition of a CrMnFeCoNi HEA after stability test. -- Fig. S10. XRD pattern of CrMnFeCoNi before and after OER stability measurements. -- Fig. S11. HRTEM image of CrMnFeCoNi after OER measurements. -- Fig. S12. In situ Raman spectra of CrMnFeCoNi during OER measurements. -- Fig. S13. High-resolution XPS spectra of CrMnFeCoNi HEA after OER stability measurements. -- Fig. S14. H2O2 yield vs. potential from MnFeCoNi, CrMnFeCoNi, CuMnFeCoNi, and Pt/C. -- Fig. S15. Relaxed atomic configuration of the four fundamental steps of OER/ORR for the MnFeCoNi structure. -- Fig. S16. Relaxed atomic configuration of the four fundamental steps of OER/ORR for the CuMnFeCoNi structure. -- Fig. S17. Galvanostatic discharge-charge curves with 10 min discharge and 10 min charge cycles at a current density of 5 mA/cm2. -- Fig. S18. Galvanostatic discharge-charge curves with 10 min discharge and 10 min charge cycles at a current density of 12 mA/cm2. -- Table S1. Atomic radius and electronegativity of different elements. -- Table S2. Mn 2p, Fe 2p, Co 2p and Ni 2p XPS binding energies of MnFeCoNi, CrMnFeCoNi, and CuMnFeCoNi. -- Table S3. Comparison of the OER performance of the CrMnFeCoNi HEA with recently reported high entropy alloy catalysts. -- Table S4. ICP-OES results of the amount of metallic elements in the electrolyte after long-term tests. -- Table S5. Comparison of the bifunctional activities of various state-of-the-art electrocatalysts for OER and ORR. -- Table S6. Comparison of the ZAB performances obtained using state-of-the-art air cathodes, Peer reviewed