Impedance Spectroscopy Operating Mechanisms of Perovskite Solar Cell CS0.05 (FA / MA)0.95Pb (I / Br)3+ CsCl

Tayyebeh Shirzad¹ Morteza Izadifard² Mohammad Ebrahim Ghazi³

1) PhD student in Condensed Matter Physics, Shahroud University of Technology
2) Associate Professor, Faculty of Physics, Shahroud University of Technology - Iran
3) Professor, Faculty of Physics, Shahroud University of Technology, Iran

Publication : 6th International Conference on Applied Researches in Science & Engineering - Germany(6carse.com)
Abstract :
The subject of stability for a long time is one of the main challenges to perovskite solar cells (PSCs) development. Therefore, an accurate understanding of the degradation mechanisms of the device is required. In this work, we use a triple cation (A = Cs / FA / MA) with a halide mixture (X = Cl / Br / I) of APbX3 compounds as a volume ratio change (x = FAPbI3 / MAPbBr3) to produce perovskite solar cells. Yields were recorded at 11.91 %/ 12.3% for perovskites with/without CsCl compounds, respectively. The highest efficiency is equal to 12.3%. Cells made with adsorbent layers x = 0.63 have better stability for 170 days, while the efficiency of cells made at x = 0.83, which was higher than other cells, 57% efficient initial after 170 days was reported. By adding the volume percentage of CsCl to the maximum efficiency sample S1 (x = 0.83), cell stability was reported to be 74% of the initial Efficiency for CsCl 1%(S4) after 170 days. The EIS characteristics show that after adding CsCl(1%), the transport resistance (R1) decreases, and the CPE1, dependant on the dielectric properties of the perovskite material, increases by about 4.9 nF. The low-frequency CPE2 increases by about 337 mF, whereas the interface-related resistance (R3) shows a 179-ohm decrease. The increase in CPE2 could be related to ions and electrons accumulation at interfaces during adding CsCl. Also, it has seen the sample x=0.63; it has excellent stability compared to the sample S1 despite its low efficiency, so we may be to consider the Nyquist chart as a predictor of stability.
Keywords : Organic hybrid halide perovskite Cs0.05 (FA / MA)0.95Pb (I / Br)3 Spin coating method Cesium chloride Perovskite solar cells Electrochemical Impedance Spectroscopy