Crystal system: triclinic
| a: | 12.2981 (±0.0007) Å |
| b: | 12.3163 (±0.0008) Å |
| c: | 17.2102 (±0.0011) Å |
| α: | 83.575 (±0.002)° |
| β: | 79.708 (±0.002)° |
| γ: | 89.976 (±0.002)° |
Starting materials: PbI2, F5-PEAI
Product: Yellow single crystals (Figure S9a)
Description: PbI2 (69.2 mg), F5-PEAI (101.7 mg), dissolved in 0.5 ml n-Butanol and 0.1 ml 57wt% stabilized HI at 95 °C. Slowly cool the solution (1 °C/hr) to room temperature. The solids were filtered and washed with ethyl ether.
Method: Single crystal X-ray diffraction
Description: Room temperature. Instrument: Bruker D8 Quest ECO diffractometer with a microfocus Mo K radiation source and Photon 50 CMOS half-plate detector. SHELXL2014 was used for refinement - more details in SI of the reference.
Comment: The structure is taken from the cif file provided by the authors. We believe that the data for (F5-PEA)2PbI4 and ((PEA)0.5(F5-PEA)0.5)2PbI4 in Table S2 of the references is switched.
Crystal system: unknown
| Band gap (fundamental), eV |
|---|
Starting materials: 2-pentafluorophenylacetonitrile, BH3, THF, HI, ether, PbI2 salt
Product: spin-coated thin film, high crystallinity
Description: First step: 5F-PEAI salt synthesized as follows: 5g of 2-pentafluorophenylacetonitrile dissolved in 80 mL of THF. 84 mL of BH3-THF slowly added and reaction allowed to reflux. 17mL of HI added before solution mixed for an hour. 350 mL of ether added, then solution precipitated into crystals. Second step (thin film formation): 2:1 5F-PEAI:PbI2 were dissolved in 4:1 DMF:DMSO solvent mixture, stirred for 30 minutes. Substrate: quartz substrate with 120 nm gold layer of interdigitated fingers. Precursor solution (0.05-0.1 molar) pipetted onto substrate and then spun at 4000 rpm for 30 seconds, targeting film thickness of 80-300nm.
Method: Electroabsorption
Description: Films were spin-coated onto interdigitated Au electrode array - 45 micron distance between opposing fingers. Samples mounted in cryostat with Cu wires soldered to opposing electrode stripes. Xe lamp light spectrally filtered, focused on sample and subsequently on UV-enhanced Si photodiode detector. Sample transmission, substrate transmission, and sample electrotransmission were collected in independent scans.Absorbance and electroabsorbance were then calculated from the respective transmissions. The fundamental gap is determined by the crossover point of absorption curves measured under different electric fields in the fundamental band gap region.
Comment: Significantly more detail in paper.
Crystal system: unknown
| Exciton binding energy, eV |
|---|
Starting materials: 2-pentafluorophenylacetonitrile, BH3, THF, HI, ether, PbI2 salt
Product: spin-coated thin film, high crystallinity
Description: First step: 5F-PEAI salt synthesized as follows: 5g of 2-pentafluorophenylacetonitrile dissolved in 80 mL of THF. 84 mL of BH3-THF slowly added and reaction allowed to reflux. 17mL of HI added before solution mixed for an hour. 350 mL of ether added, then solution precipitated into crystals. Second step (thin film formation): 2:1 5F-PEAI:PbI2 were dissolved in 4:1 DMF:DMSO solvent mixture, stirred for 30 minutes. Substrate: quartz substrate with 120 nm gold layer of interdigitated fingers. Precursor solution (0.05-0.1 molar) pipetted onto substrate and then spun at 4000 rpm for 30 seconds, targeting film thickness of 80-300nm.
Method: Electroabsorption
Description: Films were spin-coated onto interdigitated Au electrode array - 45 micron distance between opposing fingers. Samples mounted in cryostat with Cu wires soldered to opposing electrode stripes. Xe lamp light spectrally filtered, focused on sample and subsequently on UV-enhanced Si photodiode detector. Sample transmission, substrate transmission, and sample electrotransmission were collected in independent scans. Absorbance and electroabsorbance were then calculated from the respective transmissions. The exciton binding energy arises as the difference of the 1s exciton peak energy observed in conventional absorption and the fundamental gap as determined by the crossover point of absorption curves measured under different electric fields in the fundamental band gap region.
Comment: Significantly more detail in paper.
Crystal system: unknown
| Exciton energy, eV |
|---|
Starting materials: 2-pentafluorophenylacetonitrile, BH3, THF, HI, ether, PbI2 salt
Product: spin-coated thin film, high crystallinity
Description: First step: 5F-PEAI salt synthesized as follows: 5g of 2-pentafluorophenylacetonitrile dissolved in 80 mL of THF. 84 mL of BH3-THF slowly added and reaction allowed to reflux. 17mL of HI added before solution mixed for an hour. 350 mL of ether added, then solution precipitated into crystals. Second step (thin film formation): 2:1 5F-PEAI:PbI2 were dissolved in 4:1 DMF:DMSO solvent mixture, stirred for 30 minutes. Substrate: quartz substrate with 120 nm gold layer of interdigitated fingers. Precursor solution (0.05-0.1 molar) pipetted onto substrate and then spun at 4000 rpm for 30 seconds, targeting film thickness of 80-300nm.
Method: Electroabsorption
Description: Films were spin-coated onto interdigitated Au electrode array - 45 micron distance between opposing fingers. Samples mounted in cryostat with Cu wires soldered to opposing electrode stripes. Xe lamp light spectrally filtered, focused on sample and subsequently on UV-enhanced Si photodiode detector. Sample transmission, substrate transmission, and sample electrotransmission were collected in independent scans. Absorbance and electroabsorbance were then calculated from the respective transmissions.
Comment: Significantly more detail in paper.