| ICP-OES, Pd loading | 1,9 wt % |
|---|---|
| N₂ physisorption, BET surface area | 119 m² g⁻¹ |
| STEM particle-size analysis | Particles counted: 69; average Pd particle size: 3.3 nm (σ = 6.4 nm); calculated metal dispersion: 34 % |
| CO-DRIFTS, 30 min CO exposure | 2156 cm⁻¹, assigned to CO adsorbed to cationic Pdδ⁺ species; 2114 cm⁻¹, assigned to CO adsorbed to neutral low-coordinated Pd single sites; 1939 cm⁻¹, assigned to bridged CO species on larger Pd ensembles or clusters; 1628 cm⁻¹, assigned to surface bidentate carbonate species; bands were also observed at 1555 and 1436 cm⁻¹ |
| XPS, Pd 3d₅/₂ | Approximately 336.0 eV |
Fabian Rang, Birger Holtermann, Yolita Eggeler, Simon Barth, Anna Zimina, Jan-Dierk Grunwaldt, Schirin Hanf. “Support engineering with phosphorus: Tuning the palladium-catalyzed selective hydrogenation of α,β-unsaturated aldehydes.” ChemRxiv (). https://doi.org/10.26434/chemrxiv.15007916/v1
Values presented only in spectra, diffraction patterns, micrographs, elemental maps, particle-size distributions, or other plots or images were not transcribed
| ICP-OES, Pd loading; P loading | 1,8 wt %; 0,8 wt % |
|---|---|
| N₂ physisorption, BET surface area | 118 m² g⁻¹ |
| ICP-OES, Pd loading; P loading | 2,0 wt %; 2,0 wt % |
|---|---|
| N₂ physisorption, BET surface area | 116 m² g⁻¹ |
| PXRD | Extra peaks resulted from the use of regular polypropylene tape instead of cellulose-acetate tape and did not interfere with the expected peaks |
| ICP-OES, Pd loading; P loading | 1,8 wt %; 2,5 wt % |
|---|---|
| N₂ physisorption, BET surface area | 105 m² g⁻¹ |
| STEM particle-size analysis | Particles counted: 156; average Pd particle size: 2.2 nm (σ = 2.8 nm); calculated metal dispersion: 51 % |
| STEM-EDX | Phosphorus was homogeneously distributed across the support surface |
| CO-DRIFTS, 30 min CO exposure | The bridged CO band disappeared completely; linear CO adsorption bands at 2141, 2102, and 2056 cm⁻¹ dominated |
| XPS, P 2p | 134 eV |
| XPS, Pd 3d | Two contributions centered at approximately 336.0 and 337.2 eV |
| ICP-OES, Pd loading; P loading | 2,0 wt %; 3,7 wt % |
|---|---|
| N₂ physisorption, BET surface area | 112 m² g⁻¹ |
| ICP-OES, Pd loading; P loading | 1,9 wt %; 4,6 wt % |
|---|---|
| N₂ physisorption, BET surface area | 108 m² g⁻¹ |
| ICP-OES, Pd loading | 2,0 wt % |
|---|---|
| N₂ physisorption, BET surface area | 126 m² g⁻¹ |
| STEM particle-size analysis | Particles counted: 160; average Pd particle size: 9.7 nm (σ = 9.9 nm); calculated metal dispersion: 11 % |
| CO-DRIFTS, 30 min CO exposure | 1879 cm⁻¹, assigned to bridged CO species on larger metallic Pd ensembles |
| XPS, Pd 3d₅/₂ | Approximately 336.7 eV |
| ICP-OES, Pd loading; P loading | 2,0 wt %; 1,1 wt % |
|---|---|
| N₂ physisorption, BET surface area | 118 m² g⁻¹ |
| ICP-OES, Pd loading; P loading | 1,8 wt %; 2,6 wt % |
|---|---|
| N₂ physisorption, BET surface area | 98 m² g⁻¹ |
| STEM particle-size analysis | Particles counted: 269; average Pd particle size: 3.8 nm (σ = 8.2 nm); calculated metal dispersion: 29 % |
| STEM-EDX | Phosphorus was homogeneously distributed across the support surface |
| CO-DRIFTS, 30 min CO exposure | The 1879 cm⁻¹ bridged CO band became nearly undetectable; a new band at 2123 cm⁻¹ was assigned to CO adsorbed on cationic single-site Pd species |
| XPS, P 2p | 135 eV |
| XPS, Pd 3d | The signal shifted to higher binding energy, with a dominant component centered at approximately 337.8 eV |
| ICP-OES, Pd loading; P loading | 2,0 wt %; 4,8 wt % |
|---|---|
| N₂ physisorption, BET surface area | 72 m² g⁻¹ |
| ATR-IR | Characteristic P–O stretching bands were observed between 950 and 1200 cm⁻¹ |
|---|
| ATR-IR | Phosphate species could not be unambiguously identified because their characteristic vibrations overlapped with the intense Si–O–Si stretching band between 900 and 1200 cm⁻¹ |
|---|
| PXRD | Only broad diffraction peaks characteristic of amorphous SiO₂ were observed; broad reflections were assigned to Pd and PdO phases; no additional diffraction peaks were observed after phosphorus incorporation |
|---|
| PXRD | Reflections at 2θ = 37°, 40°, 46°, 60°, 67°, and 85° were assigned to the η-Al₂.₁₄₄O₃.₂ phase; only weak PdO reflections were observed; no additional diffraction peaks were observed after phosphorus incorporation |
|---|
| STEM-EDX | In several cases, the Pd signal was too weak for reliable detection; measurement times of approximately 15 min led to visible changes in particle morphology and support surface structure |
|---|