Proceedings of International Conference on Perovskite Thin Film Photovoltaics and Perovskite Photonics and Optoelectronics (NIPHO24)
Publication date: 25th April 2024
The efficiency of perovskite solar cells has been increasing steadily since their introduction in 2009 in just a few years from the construction of the first devices in this technology. Their rapid improvement over time is due to several factors, including the tunable bandgap, high absorption coefficient, and relatively easy manufacturing process, which make them a highly promising technology for future solar energy conversion. An inherent challenging issue of lead halide perovskite fabrication and further commercial application is phase stability and chemical degradation in a humid environment. Strategies to improve the stability of perovskite materials have employed various approaches, among them the use of compositional engineering based on incorporation of different cations in the A-site and different halides in the B-site. This method involves incorporating oversized organic cations to fortify the perovskite structure, thereby enhancing its stability. By strategically altering the composition of perovskites, it is possible to an significantly impact various attributes of the material, such as optical absorption, electronic band structure, thermal stability, and resistance to environmental factors. According to the Goldschmidt Tolerance Factor (t), empirical index widely used to predict perovskite structure incorporating large organic cations such as guanidinium ([(NH2)3C]+, GUA), acetamidinium (ACA) or dimethylammonium ((CH3)2NH2+, DMA) and modulating quantity and combination of ions on the X position in ABX3 formula allows for the formation of perovskite compositions.
This study presents compositional engineering of a double-cation perovskite materials based on oversized cations. Commonly used halide perovskites (MHPs) synthesis strategies are based on solution methods, require applying solvents, elevated temperatures, and producing large amounts of chemical waste. Samples reported in this study were prepared by very useful mechanochemical synthesis, driven by the mechanical force, with lots of advantages such as limiting using any harmful solvents, reducing large-energy consuming solvothermal conditions for homogeneity of chemical mixture, allowing the application of the inorganic substrates, avoiding insolubility issues.
This research was supported by the National Science Centre (grant MAESTRO 11 No. 2019/34/A/ST5/00416).