Numerical Simulation of CsSnI3-based Perovskite Solar Cells: Influence of doped-ITO Front Contact

The environmental friendliness and excellent thermal stability proves Cesium Tin Iodide (CsSnI
₃
) as one of the promising materials for the commercialization of the perovskite solar cells. However, CsSnI
₃
solar cells suffer from poor efficiency due to having low open-circuit voltage, V
_OC
attributed to poor absorber film quality as well as energy level mismatch at the interfaces between different layers like transparent front contact (typically used Indium Tin Oxide, ITO) - carrier transport layer interface. In order to improve the energy matching between ITO - hole transport layer (HTL) interface, a typical inverted planar perovskite solar cell (IT O/HT L/CsSnI
₃
/ET L) is numerically simulated (Finite difference time domain, FDTD analysis followed by electrical simulation) here, with various types of doped ITO layers having higher work functions (≥ 5eV), replacing the typical undoped ITO material having lower work function (≤ 4.7eV). The simulation results illustrate that, utilizing the higher work function and optical transparency of available doped ITO materials the V
_OC
of a typical CsSnI
₃
cell can be increased from 0.5V up to 1.1V which will make it possible to achieve power conversion efficiency as high as 11% (which is 3.3% with undoped ITO), without adopting complex modification of the absorber layer.