Synthesis and Characterization of Organic-Inorganic Layered Perovskite Compounds Using Fullerene Derivatives
Layered perovskite (RNH3)2PbI4 (R = organic cation), which contained the fullerene derivatives, [ethyl-3-tert-butoxycarbonylaminopropyl (1,2-methanofullerene C60)]-61,61-di carboxylate iodide (EAF-I) and di [3-tert-butoxycarbonylaminopropyl (1,2-methanofullerene C60)]- 61,61-dicarboxylate diiodide (DAF-I2) in the organic layers were fabricated and compared with previously reported perovkite compound containing N-methyl-2-(4-aminophenyl)-fulleropyrrolidine iodide (AmPF-I). Because the solvent solubilities of EAF-I and DAF-I2 to N,N-dimethylformamide (DMF) were higher than AmPF-I, the film processability of EAF-I and DAF-I2 was improved compared with AmPF-I. The X-ray diffraction patterns proved the construction of the perovskite structure in (EAF)2PbI4 and (AmPF)2PbI4 cast films. EAF was well-organized and closer-packing than AmPF in the perovskite structure. For the diamine-type fullerene, DAF-I2, it is difficult to form layered structure by spin-coated or cast methods. New sharp X-ray diffraction peaks were observed for DAF-I2 films dipped in PbI2 solution. The intercalations and formation of perovskite structure of (DAF)PbI4 were studied.