First principles study on opto-electronic under pressure effect of TiO2 as electron transport material for perovskites solar cells Mohamed lamine BELKHIR , Mohamed elsaid SARHANI , Ahmed GUEDDOUH
Laboratoire de Physique des Matériaux , Université Amar Telidji de Laghouat - Algérie
Abstract
The main objective behind this present research work is to study this compound TiO2 because of the large use as electron transport material for perovskites solar cells in 0 GPa and under pressure from 0 GPa to 50 GPa and study the behavior under pressure and study the properties in 0 GPa and under pressure.
Using the program (CASTEP) which uses a method of pseudo-potential, which is based on density functional theory (DFT), we calculate the properties of the structural, electronic, mechanical and optical of compound TiO2 fluorite and pyrite have used the generalized gradient approximation (GGA-PBE) to calculate the exchange and correlation potential for calculating structural properties (grid constant), electronic properties (band structure and density of states), elastic properties (elastic constants, the elastic modules) And the results obtained agreement experimental and theoretical results available.To understand the properties of materials from a microscopic point of view, we resort to the study of structural properties under normal conditions and under pressure. The application of a hydrostatic pressure hydrostatic pressure to a solid, induces a change of volume and symmetry (phase transition). The phase transition is produced when a phase becomes unstable under given thermodynamic conditions. thermodynamic conditions. The most stable phase corresponds to a minimum energy (G or Hat T=0). During this transition the internal energy will be modified, which means a modification of the equilibrium parameters, such as the lattice parameter.
