One may expect that isotopic exchange has no influence on charge carrier lifetime and perovskite solar cell performance because isotopic effects do not affect the fundamental electronic structure of materials. Experiments defy this expectation. By performing nonadiabatic (NA) molecular dynamics simulations, we demonstrate that hydrogen and deuterium exchange significantly enhances the excited-state lifetime and stability of CH₃NH₃PbI₃. Replacing lighter hydrogen with heavier deuterium suppresses the collective motions of organic and inorganic components, thus enhancing lattice stiffness and decreasing the NA coupling. Isotopic exchange further reduces NA coupling by localizing electron wave functions for separation of electrons and holes, which beats the extended coherence time, slowing down nonradiative electron–hole recombination from CH₃ND₃PbI₃ to CD₃ND₃PbI₃ with respect to the pristine system. The unchanged fundamental electronic structure together with the prolonged carrier lifetime and enhanced stability rationalize the improvement of the deuterated CH₃NH₃PbI₃ solar cells. Our work provides valuable insights into isotope effects for the design of high-performance perovskite photovoltaic and optoelectronic devices.

中文翻译：

---

同位素交换通过量子动力学模拟延长了金属铅钙钛矿中电荷载流子的寿命

人们可能希望同位素交换不会影响电荷载流子寿命和钙钛矿太阳能电池的性能，因为同位素效应不会影响材料的基本电子结构。实验违背了这一期望。通过执行非绝热（NA）分子动力学模拟，我们证明氢和氘交换显着提高了CH ₃ NH ₃ PbI ₃的激发态寿命和稳定性。。用较重的氘代替较轻的氢可抑制有机和无机组分的集体运动，从而增强晶格刚度并降低NA偶联。同位素交换进一步降低NA耦合通过定位电子波函数为电子和空穴的分离，这胜过扩展相干时间，从CH减慢非辐射的电子-空穴再结合₃ ND ₃碘化铅₃到CD ₃ ND ₃碘化铅₃相对于所述原始系统。不变的基本电子结构以及延长的载流子寿命和增强的稳定性使氘代CH ₃ NH ₃的改进合理化。PbI ₃太阳能电池。我们的工作为设计高性能钙钛矿光伏和光电器件的同位素效应提供了宝贵的见解。