See all entries for this property (5 total)
Crystal system: cubic
| a: | 6.2397 (±0.0005) Å |
| b: | 6.2397 (±0.0005) Å |
| c: | 6.2397 (±0.0005) Å |
| α: | 90° |
| β: | 90° |
| γ: | 90° |
Starting materials: Tin (II) oxide, HI (aq), ethylene glycol, argon, nitrogen
Product: Black-green powder.
Description: Dissolve Tin (II) oxide (10.40 g, 27.9 mmole) in 20 ml of a concentrate (57% by weight) HI (aq) in a test tube under flowing argon. Add another 8.0 ml of aqueous HI to a test tube containing CH3NH3-HI (4.44g, 27.9 mmole). Gently heat solution to 90.0 °C in a water/ethylene glycol bath to facilitate dissolution. Mix warm CH3NH2-HI and SNI2 solutions and cool the resulting yellow solution to room temperature. Filter the black-green precipitate that forms under flowing nitrogen and dry under flowing argon at 100 °C for 5 hr. Yield is typically 76 %. CH3NH3SnI3 is air sensitive and decomposes in air within several hours. All samples are stored and manipulated for the various measurements in an argon-filled glove box with oxygen and water levels below 1 ppm.
Method: Powder X-ray diffraction
Description: Not specified. Refer to Page 160 Experimental paragraph 1.
Comment: The reference for the assignment of the PXRD peaks is not available.
See all entries for this property (4 total)
Crystal system: unknown
| Band gap (optical, diffuse reflectance), eV |
|---|
Starting materials: CH3NH3I [from synthesis], SnI2 [from synthesis], distilled HI 57% aqueous (99.95%), H3PO2 (50% aqueous)
Product: Black MASnI3 crystals
Description: Charge 100 ml 2-necked round bottom flask with a mixture of aqueous HI (6.8 ml, 7.58M) and aqueous H3PO2 (1.7 ml, 9.14M). The liquid was degassed by passing a stream of nitrogen through it for 1 min and keeping it under a nitrogen atmosphere throughout the experiment. Dissolve SnI2 (372 mg, 1 mmol) in the mixture upon heating the flask to 120 °C using an oil bath, under constant magnetic stirring, forming a bright yellow solution. Add solid CH3NH3I (159 mg, 1 mmol). Evaporate solution to approximately half its original volume by heating at 120 °C. Discontinue stirring and leave the solution to cool back to room temperature. Upon cooling, black, elongated, rhombic dodecahedral (12 faces) crystals of the title compound were precipitated. Leave crystals to grow for a further 24 h under a nitrogen atmosphere before filtering and washing copiously with degassed EtOH. Yield 70-90%.
Method: Optical-diffuse reflectance
Description: Measurements were performed at room temperature using a Shimadzu UV-3101 PC double-beam, double-monochromator spectrophotometer operating from 200 to 2500 nm. BaSO4 was used as a nonabsorbing reflectance reference. The generated reflectance-versus-wavelength data were used to estimate the band gap of the material by converting reflectance to absorbance data according to the Kubelka−Munk equation: α/S =(1 − R)^2/2R, where R is the reflectance and α and S are the absorption and scattering coefficients, respectively. Refer to Page 9029 Figure 9.