First-Principles Modeling of Photoexcitation Dynamics in Low-Dimensional Perovskites and Double Perovskite Systems

We employ first-principles modeling to understand photoexcitation dynamics in low-dimensional perovskites and double perovskites, with implications for photovoltaic applications. We examine electronic and structural properties in two-dimensional double perovskites, establishing key structure-property relationships that correlate B- and B'-site cation electronegativity with enhanced optical activity and reduced parity-forbidden transitions. These insights contribute to improving light absorption in photovoltaic materials. Additionally, we model charge dynamics in perovskite-MOF interfaces, specifically UMCM309-a@MAPbI3 and ZrL3@MAPbI3, revealing that optimal band alignment and intraband relaxation pathways effectively capture and stabilize excited carriers. The suppression of radiative recombination in these systems enhances photostability, while robust MOF-perovskite interactions improve structural integrity under photoexcitation. Together, these findings demonstrate a computational approach to tailoring perovskite interfaces with MOFs, enhancing excited-state performance and stability for advanced energy applications.