Point defect-mediated hot carrier relaxation dynamics of lead-free FASnI₃ perovskites

Abstract

In search of the promising optoelectronic performance, we herein investigated the charge carrier dynamics of lead-free cubic phased bulk formamidinium tin triiodide (FASnI 3 ) perovskite. To gain detailed theoretical...

Hot Carrier Controlled Nitrogen Fixation Reaction in Metal-Free Boron-Anchored Aza-COF: Insight from Nonadiabatic Molecular Dynamics Simulation

“…The predominant phonon frequencies were identified at around 300 cm –1 , 1200–1400 cm –1 , and relatively a small peak at 1650 cm –1 , but the amplitudes of these frequencies are noise-like. These low amplitude modes are basically consistent with the time scale of electron–hole recombination. , Thus, the low nonadiabatic coupling and low electron–phonon coupling result in the prolonged electron–hole recombination time scale, which is sufficient for effective activation of the N 2 molecule during the nitrogen reduction process from N 2 to NH 3 .…”

“…These low amplitude modes are basically consistent with the time scale of electron−hole recombination. 39,40 Thus, the low nonadiabatic coupling and low electron−phonon coupling result in the prolonged electron−hole recombination time scale, which is sufficient for effective activation of the N 2 molecule during the nitrogen reduction process from N 2 to NH 3 .…”

Defect-Induced Bandgap Widening and Abnormal Photoluminescence in Formamidinium Tin Iodide Perovskite Microcrystals

“…Theoretical calculations suggest the low formation energies of some structural defects in FASnI 3 , such as Sn vacancy (V Sn ) and FA vacancy (V FA ) . These defects might not only act as trap states influencing the recombination of photogenerated carriers, but also could change the lattice symmetry in FASnI 3 . We therefore hypothesized that the existence of defects could make the structure of FASnI 3 different and thus lead to changes in the photophysical properties.…”

“…33 These defects might not only act as trap states influencing the recombination of photogenerated carriers, but also could change the lattice symmetry in FASnI 3 . 34 We therefore hypothesized that the existence of defects could make the structure of FASnI 3 different and thus lead to changes in the photophysical properties. If we could develop a strategy to synthesize FASnI 3 crystals with tailored defect states, we could use them as model systems for gaining deep insight into the relationship between the structure and the photophysical properties.…”

Emergence of Z-Scheme Photocatalysis for Total Water Splitting: An Improvised Route to High Efficiency

“…For studying these one can employ ab initio nonadiabatic molecular dynamics (NAMD) simulations in conjunction with suitable electronic structure theory calculations. − Different surface hopping algorithms (such as the fewest switch surface hopping and decoherence-induced surface hopping) under classical path approximation (CPA) are used for studying different exciton relaxation dynamics. Herein, the motion of the heavier ion cores is treated classically, and the electronic motions are treated through real-time time-dependent quantum mechanical treatment.…”