Investigation of instability of perovskite methyl ammonium bismuth iodide (MA3Bi2I9) thin film absorber layer and FTO/TiO2/MA3Bi2I9/P3HT/Au solar cells under stress factors

Sun is most prominent renewable energy sources. It is possible to generate both heat and electricity from solar energy. When conventional solar cells are examined, it can be seen that they are mostly silicon-based solar cells. However, the unit cost of silicon solar cells is quite high. For this reason, scientists have focused on making low-cost solar cells. Perovskite solar cells, one of the third generation solar cells, have attracted the attention of scientists with their efficiency. However, perovskite solar cells have instability and toxicity problems like Pb. Non-toxic elements that can be used instead of Pb in the periodic table have been investigated. Among these elements, the most promising is bismuth. It is possible to produce more stable, environmentally friendly, and long-lasting perovskite solar cells by using bismuth instead of lead in perovskite solar cells. This creates the potential for perovskite solar cells to compete commercially with silicon-based solar cells. In this study, MA3Bi2I9 thin films, which are perovskite solar cell optical absorber layers, were grown by thermal evaporation method and annealed at different temperatures (30°C, 80°C, 100°C, 120°C, 160°C and 200°C). Structural, morphological and optical analyzes of annealed thin films were made. The perovskite solar cell in the form of FTO/TiO2/MA3Bi2I9/P3HT/Au produced in the same way as the optical absorber layer thin film was annealed at the same temperatures and I-V data were recorded in an argon gas atmosphere. Another perovskite solar cell in the same form was kept in the laboratory atmosphere and the IV measurements taken on different days were recorded. Findings from thin film and solar cells are presented comparatively for the future production of stable MA3Bi2I9 perovskite solar cells.