Effect of the C60 electron transport layer on the perovskite solar cell performance

Perovskite solar cells are a novel class of photovoltaic materials that have attracted a lot of attention due to their excellent optoelectronic properties, simplicity and potential low manufacture cost. Perovskite solar cells are often used as a top cell in perovskite/silicon tandem solar cells. There optics play a crucial role in determining the device performance. Our optical simulations of the tandem solar cells show that the C60 layer, i. e. the most common electron transport layer used in the perovskite solar cells, has to be as thin as possible to minimize its high parasitic absorption. However, a certain thickness of the C60 layer is still needed to ensure good electrical performance. The paper analyzes the effect of the C60 layer thickness on the device performance using single-junction perovskite solar cells that enable an easier and more reproducible analysis. It is shown that the minimal C60 layer thickness needed for efficient solar cells with high fill factor is 15 nm. The power conversion efficiency of so fabricated devices is 19%. © 2019 Electrotechnical Society of Slovenia. All rights reserved.