Theoretical insights into multibandgap hybrid perovskites for photovoltaic applications

International audienceThis paper reviews some of the recent theoretical investigations on the Rashba Dresselhaus spin effects and dielectric properties of CH3NH3PbI3 hybrid perovskites and CsPbI3 all-inorganic perovskites using Density functional theory. The spin vectors rotate in the non-centrosymmetric P4mm tetragonal phase, respectively clockwise and counterclockwise, in a manner that is characteristic of a pure Rashba effect. The high frequency dielectric constants ε∞ of MAPbI3 and CsPbI3 are similar as anticipated, since large differences are only expected at very low frequency where additional contributions from molecular reorientations show off for the hybrid compounds. A first simulation of a perovskite on silicon tandem cell, including a tunnel junction, is also investigated. Effect of halogen substitution (I/Br) is inspected, revealing limitations for short-circuit current and open-circuit voltage electrical characteristics