Crystal system: triclinic
| a: | 11.1463 (±0.0003) Å |
| b: | 11.2181 (±0.0003) Å |
| c: | 17.6966 (±0.0005) Å |
| α: | 99.173 (±0.001)° |
| β: | 104.634 (±0.001)° |
| γ: | 89.999 (±0.001)° |
Starting materials: PbCl2, HCl, methanol, phenethylamine
Product: Small block-like crystals to larger plate-like crystals
Description: Layered solution approach. Grow crystals within a long, straight, glass tube (Refer to Fig. 1). First dissolve 1.0 mmol (0.278 g) of freshly sublimed PbCl2 (Aldrich; 99.999%) in 7.5 ml concentrated (37 wt %) aqueous HCl (Aldrich; 99.999%). Weigh and add PbCl2 to the tube in an argon-filled glove box, with oxygen and water levels maintained below 1 ppm. Cover the tube with a septum before removing the glove box and adding HCl with a syringe. Create a second layer in the crystal tube by gently syringing 15 ml of methanol (Aldrich; anhydrous, 99.8%) on top of the HCl/PbCl2 solution. A relatively sharp interface can be created between the solvent layers due to density differences. On top of the column, add a stoichiometric amount (2 mmol or approximately 0.25 ml) of phenethylamine with a syringe. In the experiment, the phenethylamine rapidly dispersed in the methanol but, because of the sharp interface with the HCl solution, formation of the final (C6H5C2H4NH3)2PbCl4 product was very slow. The crystals were isolated after approximately one year by removing the solvent with a syringe and drying the crystals under vacuum at room temperature and later stored in an argon glove box.
Method: Single-crystal X-ray diffraction
Description: A colorless single crystal of dimensions 0.09 mm X 0.18 mm X 0.27 mm was used. A full sphere of data was collected at room temperature on a Bruker SMART CCD diffractometer, equipped with a normal focus 2.4 kW sealed tube X-ray source (Mo Kα radiation, λ = 0.71073 Å). Refer to page 695 for details.
Comment: Refer to Table 2 for the positional data
Starting materials: (PEA)2PbCl4 crystals, DMF, quartz substrates
Product: Thin film on quartz
Description: Dissolve the 2D single crystals into DMF at a concentration 6%∼10% relative to the total weight. Spin-coat at 3000 rpm for 30 s on quartz substrates. Anneal in air at 100 °C for 10 min before measurement.
Method: Photoluminescence
Description: The photoluminescence spectra were measured using a Horiba-Jobi-Yvon LabRAM ARAMIS system, with a 325 nm He-Cd laser excitation. The laser beam was collimated and focused through a 40X UV objective onto the sample surface at room temperature. Refer to figure 5.
Crystal system: triclinic
| Photoluminescence peak position, nm |
|---|
Starting materials: (PEA)2PbCl4 crystals, DMF, quartz substrates
Product: Thin film on quartz
Description: Dissolve the 2D single crystals into DMF at a concentration 6%∼10% relative to the total weight. Spin-coat at 3000 rpm for 30 s on quartz substrates. Anneal in air at 100 °C for 10 min before measurement.
Method: Photoluminescence
Description: The photoluminescence spectra were measured using a Horiba-Jobi-Yvon LabRAM ARAMIS system, with a 325 nm He-Cd laser excitation. The laser beam was collimated and focused through a 40X UV objective onto the sample surface at room temperature. Refer to figure 5.
See all entries for this property (2 total)
Starting materials: (PEA)2PbCl4 crystals, DMF, quartz substrates
Product: Thin film on quartz
Description: Dissolve the 2D single crystals into DMF at a concentration 6%∼10% relative to the total weight. Spin-coat at 3000 rpm for 30 s on quartz substrates. Anneal in air at 100 °C for 10 min before measurement.
Method: UV-Vis absorption
Description: Optical absorption spectra were obtained using a Shimadzu UV-3600 spectrophotometer.
Crystal system: unknown
| Band gap (fundamental), eV |
|---|
Starting materials: PEACl salt, PbCl2 salt, stoichiometric ratio 2:1
Product: spin-coated thin film
Description: Starting materials dissolved in 4:1 DMF:DMSO solvent mixture, stirred for 30 min at room temperature. Substrate: Quartz substrate with 120 nm gold layer with inerdigitated fingers. Precursor solution (0.1-0.3 molar) pipetted onto substrate and spin-coated, 4000 rpm / 30 seconds, targeting film thicknesses 80-300 nm.
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: PEACl salt, PbCl2 salt, stoichiometric ratio 2:1
Product: spin-coated thin film
Description: Starting materials dissolved in 4:1 DMF:DMSO solvent mixture, stirred for 30 min at room temperature. Substrate: Quartz substrate with 120 nm gold layer with inerdigitated fingers. Precursor solution (0.1-0.3 molar) pipetted onto substrate and spin-coated, 4000 rpm / 30 seconds, targeting film thicknesses 80-300 nm.
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: PEACl salt, PbCl2 salt, stoichiometric ratio 2:1
Product: spin-coated thin film
Description: Starting materials dissolved in 4:1 DMF:DMSO solvent mixture, stirred for 30 min at room temperature. Substrate: Quartz substrate with 120 nm gold layer with inerdigitated fingers. Precursor solution (0.1-0.3 molar) pipetted onto substrate and spin-coated, 4000 rpm / 30 seconds, targeting film thicknesses 80-300 nm.
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.