The influence of compression on the lattice stability of α-FAPbI₃ revealed by numerical simulation

Abstract

The ambient stability of α-FAPbI3 perovskite remains one of the biggest barriers to the commercialization, despite many attempts to enhance its lifetime. Due to the difficulties in experimenting the transition...

Hindered Phase Transition Kinetics of α‐CsPbI3 by External Tension

“…Numerical Simulations: It is necessary to simulate the phase transition of each unit cell of the CsPbI 3 structure, as the elements such as I and Pb were shared by the surroundings, leading to alteration in the thermodynamic energy, whose value was assigned to each unit cell and simulated as the transition proceed. As depicted by the classical kinetic equation, [37,41] the transition rate can be given by the attempting frequency (v) times the exponential of the minus activation energy divided by Boltzmann constant times Kelvin temperature. [42] Therefore, the time step in the modeling work was set to be 1/v, which also equals one iteration in the simulation.…”

“…It is therefore the purpose of the current research to resolve this challenge by numerical simulation, which enables us to explore the details of every stage of the phase transition that may be much harder to achieve by the experimental method. [35][36][37] It has been discovered that the presence of external strain is able to assist the Cs ions in supporting the cubic structure of perovskite, lowing effectively the driving force of phase transition. As a result, the lifetime of the α-CsPbI 3 at room temperature can be extended up to four times under hydrostatic tension.…”

Controlled formation of ball-milled carbon quantum dots via optimized graphite structures by numerical simulation

“…. [26][27][28][29] When the absolute value of P reaches 1, the vdW bond is broken, and the graphite is exfoliated. The P value for this specific site ceases to change, whose color was also set as blue and green for P = 1 and À1, respectively.…”

“…25 As the strain propagates, the P values at all sites could thus be determined by including the additional term of . 26–29 When the absolute value of P reaches 1, the vdW bond is broken, and the graphite is exfoliated. The P value for this specific site ceases to change, whose color was also set as blue and green for P = 1 and −1, respectively.…”

Atomic Structure and Dynamics of Organic–Inorganic Hybrid Perovskite Formamidinium Lead Iodide

“…The hybrid organic–inorganic halide perovskites have attracted intense attention in recent years, − because of their exceptional semiconducting properties, including long carrier lifetime, − strong absorption coefficient, − high mobility, , low defect concentration, − and tunable band gaps. − These excellent properties have been confirmed to be closely related to the dynamics of organic cations and the motion of the inorganic octahedral framework. − Among them, the sublattice of cation clusters has a unique liquidlike disorder, which is in sharp contrast to the behavior observed in conventional semiconductors. − …”