A First-Principles Study on the Structural and Carrier Transport Properties of Inorganic Perovskite CsPbI3 under Pressure

Lead halide perovskite has attracted intensive attention for pressure and strain detection. Principally, pressure-induced changes in the structure and resistance of perovskite may bring great potential for developing high-performance piezoresistive pressure sensors. Herein, for the first time, we study the structural changes and the hot carrier cooling process of perovskite CsPbI3 under pressure based on density functional theory and time-dependent density functional theory. The calculation results show that the lattice constant of CsPbI3 linearly decreases and the time and path of the hot carrier cooling process change apparently under pressure. Meanwhile, the pressure will change the transition dipole moment, and the position of the k-point will not affect the optical properties of perovskite. Subsequently, the electrical conductivity enlarges as the pressure increases due to the change in charge density caused by pressure, which will be helpful for its potential application in the pressure sensors.