Starting materials: Hydroiodic acid (HI, 57% w/w in water, Alpha Aesar), Lead oxide (PbO, 99%, Sigma-Aldrich), Methylammonium Iodide (MAI, >99%, Dyesol), Phenylethylamine (PEA)
Product: Red (PEA)2MAPb2I7 crystals
Description: 6 mmol PbO, 18 mmol MAI, and 1 mmol PEA are dissolved in HI in a 20 mL vial at 90 °C. The vial was then kept in an oven at 110 °C for 4 h. The solution was then slowly cooled to room temperature.
Method: Photoluminescence
Description: For steady-state PL measurements, the details are not available in the paper.