| Photoluminescence, bulk films, front excitation | Only PSK: 795 nm; only NC: 630 nm; PSK_NC: 670 nm; PSK_NC_Washed: 705 nm, with secondary humps at 590 and 760 nm |
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| Photoluminescence, bulk films, back excitation | Only PSK: 770 nm; only NC: 630 nm; PSK_NC: 760 nm, with secondary peaks at 620 and 690 nm; PSK_NC_Washed: 770 nm, with secondary peaks at 670 and 580 nm |
| Photoluminescence-derived bromide concentration, bulk films | PSK_NC: approximately 40 % under front excitation; PSK_NC_Washed: 30 % under front excitation |
| Photoluminescence, thin films, front excitation | Only PSK: approximately 790 nm; PSK_NC: approximately 765 nm with a secondary peak at 640 nm; PSK_NC_Washed: approximately 730 nm with a secondary peak at approximately 655 nm |
| Photoluminescence, thin films, back excitation | PSK_NC: approximately 750 nm with a secondary peak at approximately 630 nm; PSK_NC_Washed: approximately 755 nm with a secondary shoulder at approximately 620 nm |
| Photoluminescence-derived bromide concentration, thin films | Front excitation: 15 % for PSK_NC and 20 % for PSK_NC_Washed; back excitation: 13 % for PSK_NC and 10 % for PSK_NC_Washed |
Poyoja Rout, Chaya Kerkera, Sarang Mashale, Smruti Ranjan Panda, Laxman Gouda, Ritika Dey, Vivek Tiwari, Aditya Sadhanala. “Halide exchange via perovskite nanocrystals for interfacial defect passivation in solar cells.” ChemRxiv (). https://doi.org/10.26434/chemrxiv.15007814/v1
Values presented only in photoluminescence, UV–visible absorption, transient-absorption, XRD, XPS, UPS, KPFM, SEM-EDS or photovoltaic plots or images were not transcribed. Photovoltaic performance was not transcribed. The main paper refers to supporting information, but no separate supporting information file was available on the ChemRxiv article page
| SEM | The nanocrystal-coated film showed uniform surface topography with few voids and pinholes; nanocrystals remained visible after chlorobenzene washing |
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| XRD | Pristine-film reflections assigned to (110), (012), (021), and (202) occurred at 14.4°, 20.28°, 24.82°, and 28.66° 2θ; after nanocrystal deposition, the corresponding reflections occurred at 14.23°, 20.13°, 24.67°, and 28.5° 2θ |
| UV–visible absorption | Pristine and nanocrystal-coated perovskite films showed broad absorption from the ultraviolet to near-infrared region; the pristine film had moderately higher absorbance; the nanocrystal film had substantially lower absorbance |
| Tauc-plot optical band gap | 1.500 eV for pristine perovskite, 1.495 eV for nanocrystal-coated perovskite, and 1.489 eV after solvent washing |
| XPS, pristine perovskite | I 3d peaks at 618.85 eV (I 3d₅/₂) and 630.31 eV (I 3d₃/₂); Br 3d peaks at 68.01 and 69.07 eV; Br:I atomic ratio 0.1054:1 |
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| XPS, pristine nanocrystals | Br:I atomic ratio 2.285:1 |
| XPS, PSK+NC | Br:I atomic ratio 0.2301:1 |
| XPS, PSK+NC after washing | Br:I atomic ratio 0.1506:1 before Ar-ion etching and 0.1083:1 after 60 s Ar-ion etching; etching attenuated the Br 3d signal and increased I 3d peaks at 618.73 and 630.21 eV |
| KPFM and UPS, only NC | KPFM −4.78 eV; UPS low cutoff −17.57 eV; Fermi energy −3.65 eV; VBM −5.35 eV; possible CBM −3.40 eV |
| KPFM and UPS, only PSK | KPFM −5.23 eV; UPS low cutoff −16.95 eV; Fermi energy −4.27 eV; VBM −5.80 eV; possible CBM −4.31 eV |
| KPFM and UPS, PSK+NC | KPFM −5.21 eV; UPS low cutoff −17.32 eV; Fermi energy −3.90 eV; VBM −5.47 eV; possible CBM −3.98 eV |
| KPFM and UPS, PSK+NC after washing | KPFM −5.14 eV; UPS low cutoff −16.53 eV; Fermi energy −4.69 eV; VBM −5.02 eV; possible CBM −3.53 eV |
| Transient absorption | The ground-state bleach evolved from approximately 714–718 nm at delays below 300 fs to a narrower band near approximately 754 nm by 400 ps; the fast sub-picosecond dynamics reflected cooling of carriers initially occupying states approximately 70 meV above the perovskite band edge, Eg approximately 1.64 eV; red-shifting and narrowing were most prominent for PSK1; at 100 ps, a red-edge excited-state-absorption signal near 800 nm occurred only for PSK1 and was absent in PSK2 and suppressed in PSK3 |
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