Defect Management Through Additive Engineering and Light Soaking in Sn-Based Perovskite Solar Cells and LEDs

Halide perovskite solar cells have revolutionized the photovoltaic field in the last decade. In a decade of intensive research it has been a huge improvement in the performance of these devices, however, the two main drawbacks of this system, the use of hazardous Pb and the long term stability, still to be open questions that have not been fully addressed. The photoconversion performance of perovskite solar cells containing alternative metals to Pb is significantly lower than the reported for devices containing Pb, where Sn-based perovskite solar cells is the alternative reporting higher photovoltaic performance close to 14%. Nevertheless, Sn-based perovskite solar cells exhibit a long term stability lower than their Pb containing counterparts, making stability their main problem. In this talk, we highlight how the use of proper additives and light soaking for defect engineering can increase significantly the stability of formamidinium tin iodide (FASnI₃) solar cells, and discuss about the different mechanism affecting this stability, beyond the oxidation of Sn²⁺, and how they can be countered. Effect in Sn-based perovskite LEDs will be also analyzed.