| TEM and DLS | Faceted nanocrystals with an average particle size of approximately 10 nm |
|---|---|
| Powder XRD | The phase-pure tetragonal chalcopyrite CuFeS₂ phase was observed |
| UV–visible–NIR absorption, hexane | A prominent optical resonance band was centered at 500 nm |
| EDX | Cu, Fe, and S were present in ratios consistent with the expected CuFeS₂ composition; no peaks from oxidized phases or impurities were detected |
| Raman spectroscopy, dried on Si | Chalcopyrite lattice vibrations were observed at 250–350 cm⁻¹; no impurity of different phases or defects was observed |
Shashank K. Gahlaut, Biswajit Bhattacharyya, Guilherme Carraro Carella, Gino Wegner, Evgenii Titov, Felix Stete, Laura Baier, Radwan M. Sarhan, Peter Saalfrank, Andreas Taubert, Matias Bargheer, Kurt Busch, Ilko Bald. “Light-driven electron-transfer catalysis on earth-abundant CuFeS₂ nanocrystals probed by operando SERS.” ChemRxiv (). https://doi.org/10.26434/chemrxiv.15007925/v1
Values presented only in micrographs, size histograms, spectra, diffraction patterns, time series, or other plots or images were not transcribed. Excitation-dependent SERS signal-performance comparisons were not retained. The main paper refers to supporting information, but no separate supporting information file was available on the ChemRxiv article page
| SERS, 1 µM BPE, 488, 532, 633, and 785 nm excitation | The excitation wavelengths yielded structurally identical vibrational profiles. No discernible fluctuations in peak positions were observed during time-resolved monitoring |
|---|---|
| Raman and SERS, 488 nm excitation | The pristine substrate had no background Raman or photoluminescence signal from 800 to 1800 cm⁻¹; the dominant BPE band was the C=C ethylene stretching mode at 1640 cm⁻¹ |
| SERS, 457–785 nm excitation | At 488 and 532 nm, the NTP band at 1335 cm⁻¹ was followed by the DMAB band at 1442 cm⁻¹ and subsequent thermal desorption of DMAB |
|---|---|
| Time-dependent SERS, 457 nm excitation | DMAB bands near 1140, 1390, and 1442 cm⁻¹ appeared and progressively intensified with illumination time; the NTP NO₂ stretching mode at 1335 cm⁻¹ and the DMAB ag mode at 1442 cm⁻¹ were used for time tracking |
| SERS, irradiation longer than 500 s | No evidence of further reduction of DMAB to p-aminothiophenol was observed |
| SERS, 488 nm excitation, 1 mW | The characteristic DMAB modes decreased while broad bands centered at approximately 1350 and 1580 cm⁻¹ emerged; the bands were assigned to the D and G bands of amorphous carbon |
| Raman spectroscopy after dark heating, up to 145 °C for 5 min, 633 nm excitation, 7.6 kW cm⁻², 10 s acquisition | No characteristic DMAB peaks were observed |