Abstract We replaced Pb with nontoxic Cu metal for lead-free perovskite solar cells and investigated their potential for solar cell applications. The ionic dynamics of the NH3(CH2)2NH3CuCl4 crystal are investigated as a function of temperature, with a focus on the role of the NH3(CH2)2NH3+ cation. This investigation was conducted by 1H and 13C MAS NMR experiments. The contributions to the NMR chemical shifts are correlated to the distribution of the spin density in the ligand moiety. The 1H NMR chemical shift for NH3 changes more significantly with the temperature than that for CH2. This change in the cationic motion is enhanced at the N-end of the organic cation, which is fixed at the inorganic layer by N–H⋯Cl hydrogen bonds. In addition, the molecular motions are discussed in terms of the spin-lattice relaxation time, which reveal that the CH2 ion located in the middle of the N–C–C–N bond undergoes tumbling motion according to the Bloembergen–Purcell–Pound theory.

中文翻译：

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MAS NMR 显示钙钛矿层状晶体 NH3(CH2)2NH3CuCl4 中 NH3(CH2)2NH3 阳离子的动力学

摘要 我们用无毒的铜金属代替铅用于无铅钙钛矿太阳能电池，并研究了它们在太阳能电池应用中的潜力。研究了 NH3(CH2)2NH3CuCl4 晶体的离子动力学与温度的关系，重点是 NH3(CH2)2NH3+ 阳离子的作用。该研究是通过 1H 和 13C MAS NMR 实验进行的。对 NMR 化学位移的贡献与配体部分中的自旋密度分布相关。NH3 的 1H NMR 化学位移随温度的变化比 CH2 更显着。这种阳离子运动的变化在有机阳离子的 N 端增强，它通过 N–H⋯Cl 氢键固定在无机层上。此外，分子运动是根据自旋晶格弛豫时间讨论的，