Electron–Rotor Interaction in Organic–Inorganic Lead Iodide Perovskites Discovered by Isotope Effects

详细信息    查看全文

• 作者：Jue Gong ; Mengjin Yang ; Xiangchao Ma ; Richard D. Schaller ; Gang Liu ; Lingping Kong ; Ye Yang ; Matthew C. Beard ; Michael Lesslie ; Ying Dai ; Baibiao Huang ; Kai Zhu ; Tao Xu
• 刊名：The Journal of Physical Chemistry Letters
• 出版年：2016
• 出版时间：August 4, 2016
• 年：2016
• 卷：7
• 期：15
• 页码：2879-2887
• 全文大小：501K
• 年卷期：0
• ISSN：1948-7185

文摘

We report on the carrier–rotor coupling effect in perovskite organic–inorganic hybrid lead iodide (CH₃NH₃PbI₃) compounds discovered by isotope effects. Deuterated organic–inorganic perovskite compounds including CH₃ND₃PbI₃, CD₃NH₃PbI₃, and CD₃ND₃PbI₃ were synthesized. Devices made from regular CH₃NH₃PbI₃ and deuterated CH₃ND₃PbI₃ exhibit comparable performance in band gap, current–voltage, carrier mobility, and power conversion efficiency. However, a time-resolved photoluminescence (TRPL) study reveals that CH₃NH₃PbI₃ exhibits notably longer carrier lifetime than that of CH₃ND₃PbI₃, in both thin-film and single-crystal formats. Furthermore, the comparison in carrier lifetime between CD₃NH₃PbI₃ and CH₃ND₃PbI₃ single crystals suggests that vibrational modes in methylammonium (MA⁺) have little impact on carrier lifetime. In contrast, the fully deuterated compound CD₃ND₃PbI₃ reconfirmed the trend of decreasing carrier lifetime upon the increasing moment of inertia of cationic MA⁺. Polaron model elucidates the electron–rotor interaction.