Optimizing Molecular Passivation in MAPbI₃ Perovskites: Impact of Dipole Moments and Structural Parameters

In the realm of perovskite materials, organic molecules situated at the A site play a critical role in stabilizing the structure through specific orientations and weak interactions with the inorganic framework. These polar interactions significantly influence the optoelectronic properties of perovskites, and the introduction of polar molecules can disrupt the inherent polarization, thereby altering the material performance. The research primarily focuses on the relationship between the length and width of these organic cations and their polar inductive effects. Overall, the interplay between the chain length, molecular width, and dipole moments was shown to significantly affect the lifetime of MAPbI₃ materials. Key findings indicate that non-radiative recombination, which is a major energy loss mechanism in solar cells, is intrinsically linked to the variations of hydrogen bonds and PbI₆ octahedral distortion. The analysis revealed a strong negative correlation between octahedral angles, highlighting the complex relationship between these variables and their collective effects on charge carrier dynamics.