Numerical Modeling and Analysis of HTM-Free Heterojunction Solar Cell Using SCAPS-1D

Abstract

In this research paper, a HTM-free perovskite solar cell (PSC) structure with Titanium (TiO2), methyl ammonium lead triiodide (CH3NH3PbI3) and platinum (pt) as electron transport material (ETM), photon harvester and metal back contact is proposed. Solar Cell Capacitance Simulator (SCAPS-1D) program was used to implement the model and simulation. Effect of parameters such as thickness of ETM, thickness of absorber, doping concentration of ETM & absorber and electron affinity (EA) of ETM were investigated systematically. From the obtained results, it was found that the parameters affect the performance of the solar cell. When the thickness of ETM was varied from 0.02 to 0.10 μm. The results show that photovoltaic parameters decrease with the thickness increase. When the thickness of the absorber was varied from 0.1 to 1.0 μm, the optimized value was found at thickness of 0.4 . When the doping concentration of absorber and EMT were varied from 1010–1017 cm-3 and from 1015–1020 cm-3, the highest values of PCEs were obtained at 1016 cm-3 and 1020 cm-3 for Absorber and ETM. Also when the EA was varied in the range of 3.7 eV to 4.5 eV, the optimized value was at 3.7 eV. Upon optimization of the above mentioned parameters, power conversion efficiency (PCE) was found to be 25.75 %, short circuit current density (Jsc) 23.25 mAcm-2, open circuit voltage (Voc) 1.24 V and fill factor (FF) 89.50 %. The optimized result shows an improvement of ~1.95 times in PCE, ~1.06 times in Jsc, ~1.44 times in Voc and ~1.28 times in FF as compared to the initial device with the following parameters, PCE=13.22 %, Jsc=21.96 mAcm−2, Voc=0.86 V and FF=69.94 %.

Keywords

• perovskite solar cells
• HTM free
• device modeling
• simulation
• band gap offset