In this work, the effect of some parameters on tin-based perovskite (CH3NH3SnI3) solar cell were studied through device simulation with respect to adjusting the doping concentration of the perovskite absorption layer, its thickness and the electron affinities of the electron transport medium and hole transport medium, as well as the defect density of the perovskite absorption layer and hole mobility of hole transport material (HTM). A device simulator; the one-dimensional Solar Cells Capacitance Simulator (SCAPS‑1D) program was used for simulating the tin-based perovskite solar cells. The current-voltage (J-V) characteristic curve obtained by simulating the device without optimization shows output cell parameters which include; open circuit voltage (Voc) = 0.64V, short circuit current density (Isc) = 28.50mA/, fill factor (FF) = 61.10%, and power conversion efficiency (PCE) = 11.30% under AM1.5 simulated sunlight of 100mW/cm2 at 300K. After optimization, values of the doping concentration, defect density, electron affinity of electron transport material and hole transport material were determined to be: 1.0x1016cm-3, 1.0x1015cm-3, 3.7 eV and 2.3 eV respectively. Appreciable values of solar cell parameters were obtained with Jsc of 31.38 mA/cm2, Voc of 0.84 V, FF of 76.94% and PCE of 20.35%. when compared with the initial device without optimization, it shows improvement of ~1.10 times in Jsc, ~1.80 times in PCE, ~1.31 times in Voc and ~1.26 time in FF. The results show that the lead-free CH3NH3SnI3 perovskite solar cell which is environmentally friendly is a potential solar cell with high theoretical efficiency of 20.35%.
Influence of defect density and layer thickness of absorption layer on the performance of tin based perovskite solar cell
