| EDS | The compositions of all samples were close to the nominal Pt5MnFeCoNiCu composition |
|---|---|
| PXRD, 300 and 350 °C syntheses | A single fcc phase described the diffraction patterns |
| PXRD, 400, 550, and 700 °C syntheses | Additional peaks confirmed the onset of atomic ordering into the fct intermetallic; the relative intensity ratio of the (110) peak at ~3.7° 2θ and the (111) peak at ~4.3° 2θ increased with synthesis temperature |
| PXRD refinement, HESOSO | Crystallite sizes ranged from 4.5 to 5.5 nm |
| PXRD refinement, HEI | Fcc crystallite sizes ranged from 2.8 to 4.5 nm and intermetallic-phase crystallite sizes ranged from 9 to 20 nm |
Nicolas Schlegel, Martin L. Lundquist, Tim Kunzmann, Ina Reichmann, Stefanie Punke, Jens Edelvang-Pejrup, Laura G. Graversen, Frederik L. Johansen, Emil L. Boesen, Henrik H. Kristoffersen, Katsuyoshi Kakinuma, Karl J. J. Mayrhofer, Serhiy Cherevko, Jan Rossmeisl, Matthias Arenz, Kirsten M. Ø. Jensen. “Strain anisotropy as a design principle for high-entropy intermetallic oxygen reduction catalysts.” ChemRxiv (). https://doi.org/10.26434/chemrxiv.15007838/v1
Values presented only in PXRD, EDS, electrochemical, on-line ICP-MS, operando X-ray-total-scattering, or pair-distribution-function plots or images were not transcribed. Catalyst-dissolution durability results were not retained. The main paper refers to supporting information, but no separate supporting information file was available on the ChemRxiv article page
| Operando X-ray total scattering, HESOSO | The fcc structure persisted; the lattice parameter decreased to 3.920 Å during conditioning and increased to 3.932 Å by the end of the accelerated stress test; crystallite size increased from 3.0 to 3.3 nm after electrolyte introduction and to 3.6 nm after 2000 steps, then plateaued |
|---|---|
| Operando X-ray total scattering, HEI | The fct structure persisted; the refined fcc lattice parameter ended at 3.910 Å; initial fcc and fct crystallite sizes were approximately 3.4 and 16 nm, respectively; the fcc size remained nearly constant and the fct size increased from approximately 16 to 19 nm |
| Pair distribution function and Pearson correlation analysis | The local structure of both samples remained unchanged throughout the protocol |