[5p-PA3-1~46] 12.5 Organic solar cells

[5p-PA3-20] Theoretical Study on Rotational Controllability of Organic Cations in Perovskites

〇(D)Shohei Kanno¹, Yutaka Imamura¹, Masahiko Hada¹ (1.Tokyo Metropolitan Univ.)

Keywords:Rotational motions of organic cations, Alternative perovskites, First-principle calculations

Recently, not only methylammonium lead iodide (CH₃NH₃PbI₃), but also formamidinium lead iodide (HC(NH₂)₂PbI₃) perovskite solar cell is studied. In this study, we comprehensive examined rotational barriers of HC(NH₂)₂⁺ (FA) in FAPbI₃ and the alternative perovskites, FAPbX₃ (X = Br or Cl) and FASnX₃ (X = I, Br, or Cl), and compared the rotational barriers of CH₃NH₃⁺ (MA), from first-principle calculations. We found that the rotational potential surfaces of FA show a large anisotropy, which does not appear in MA-based perovskites. Our results suggest that the direction of FA rotational motion is controllable.