| Abstract [eng] |
Perovskite solar cell (PSC) technology has been rapidly advancing over the past decade due to its good properties for charge generation and cheap reproduction value. The main goal of this master thesis is to investigate the impact of cesium on photoactive perovskite layers and to derive with efficient solutions and production sequence for highly effective solar cells that could be used in tandem with crystalline silicon photoactive layers. Due to initial imperfections of perovskite layers, alternative perovskite precursor solution manufacturing methods were explored for the formation of (FTO/TiO2/PEROVSKITE/Spiro-MeOTAD/Au) solar cell structures. Optical transmission measurements were used to evaluate the formation of perovskite layers by observing the changes in characteristic direct absorption slopes. Layer thickness was determined by taking SEM photographs and VACh measurements were used to determine the main photoelectric parameters. In addition, perovskite film photoluminescence differences were studied with perovskites being formed on TiO2 and Mg0.2Zn0.8O electron transport layers. PSCs fabricated by using an improved method of a perovskite formation generated average current densities of 30.86 mA/cm2, Voc = 1,09 V, FF = 46.34%, PCE of 17.05%. Photoluminescence spectrum analysis showed that these layers can be described by the sum of 2 gaussian curves with high accuracy of the model R2>0,999. While the Jsc is of very high value, further research of ohmic contact resistance between the charge transport layers is required to improve the FF values, which ultimately reduce the overall efficiency of these cells. We conclude that: Cesium iodide has a positive effect on the formation of perovskite layers and improves their optical and photoelectric properties; Highest average conversion efficiency values were reached for PSCs fabricated with 6% CsI content in precursor solution. The conversion efficiency of the best solar cell was 18.32%, open circuit voltage - 1.09 V, and the short-circuit current was 30.86 mA/cm2. The optimal amount of CsI for the formation of perovskite layers was found to be in the range of 6% ≤ x <7%; • The optical properties of the perovskite layer grown on MgZnO were better than of those grown on TiO2. However, the obtained photoelectric properties of a PSC with MgZnO layer were worse. |
