Structurally Tailored Organic−Inorganic Perovskites: Optical Properties and Solution-Processed Channel Materials for Thin-Film Transistors

作者：David B. Mitzi, Christos Dimitrakopoulos, Laura L. Kosbar · 发表于：Chemistry of Materials · 年份：2001 · DOI：10.1021/cm010105g · 被引用次数：381 · 研究领域：Perovskite Materials and Applications、Organic and Molecular Conductors Research、Luminescence Properties of Advanced Materials

The structures, optical properties, and field-effect mobilities of three semiconducting m -fluorophenethylammonium-based (C 6 H 4 FC 2 H 4 NH 3 ) 2 SnI 4 perovskites ( m = 2, 3, or 4) are reported and compared with the analogous measurements for the nonfluorosubstituted phenethylammonium system, (C 6 H 5 C 2 H 4 NH 3 ) 2 SnI 4 . The (4-fluorophenethylammonium) 2 SnI 4 system adopts a fully ordered monoclinic ( P 2 1 / c ) cell with the lattice parameters a = 16.653(2) Å, b = 8.6049(8) Å, c = 8.7551(8) Å, β = 98.644(2)°, and Z = 2. Both (3-fluorophenethylammonium) 2 SnI 4 and (2-fluorophenethylammonium) 2 SnI 4 are refined in a monoclinic ( C 2 /c ) subcell with the lattice parameters a = 34.593(4) Å, b = 6.0990(8) Å, c = 12.254(2) Å, β = 103.917(2)°, and Z = 4 and a = 35.070(3) Å, b = 6.1165(5) Å, c = 12.280(1) Å, β = 108.175(1)°, and Z = 4, respectively. Each hybrid structure consists of sheets of corner-sharing distorted SnI 6 octahedra separated by bilayers of fluorophenethylammonium cations. The dominant low energy feature in the optical absorption spectra for spin-coated films of the new hybrids (an exciton band associated with the tin(II) iodide framework) shifts from 609 to 599 nm and 588 nm across the series m = 4 to 2 (the corresponding value for the phenethylammonium-based system is 609 nm). This shift in optical properties is primarily attributed to subtle structural modifications induced by the organic cation substitutions, including a progressive shift in Sn−I−Sn...