Solar cells and photovoltaics can greatly benefit from the use of perovskites, a class of materials with distinct crystal structures. One of these materials is lead triodide (FAPbI3), a perovskite that shows a long transporter lifetime and high transporter portability, as well as great light retention and electrical conductivity.
Solar cells with an “inverted” structure, which is simpler than a conventional structure and more resistant to device defects, have also been the subject of energy engineers’ evaluations. While their resilience to imperfections could make upset sun-oriented cells in view of FAPbI3 more steady than sun-based cells with a normal construction, their power efficiencies have so far been generally below the laid-out focus of 25%.
A design strategy that could reduce defects in FAPbI3-based solar cells and improve their power efficiency has recently been introduced by researchers at Huazhong University of Science and Technology and other institutes in China. An additive and a coating agent are applied to the perovskite films that are integrated into solar cells as part of this strategy, which was presented in a paper that was published in Nature Energy.
“Power conversion efficiencies of inverted perovskite solar cells (PSCs) based on methylammonium- and bromide-free formamidinium lead triiodide (FAPbI3) perovskites continue to lag behind PSCs with a regular configuration. We increase the bulk and surface quality of FA0.98Cs0.02PbI3 perovskite films to close the efficiency gap.”
Rui Chen, Jinan Wang, and their colleagues wrote in their paper.
“Power change efficiencies of upset perovskite sun-oriented cells (PSCs) in light of methylammonium and sans bromide formamidinium lead triiodide (FAPbI3) perovskites still fall behind PSCs with a customary setup,” Rui Chen, Jinan Wang, and their partners wrote in their paper. “We work on the nature of both the mass and surface of FA0.98Cs0.02PbI3 perovskite movies to diminish the proficiency hole.”
To work on the presentation of transformed PSCs in view of FAPbI3, the scientists added a compound to the mass material that could decrease the deformities inside it. This compound, called dibutyl sulfoxide (DBSO), has low instability and synthetically cooperates with certain materials, impacting their properties or construction.
“In the first place, we use DBSO, a Lewis base-added substance, to work on the crystallinity and lessen the deformity thickness and inside remaining pressure of the perovskite mass,” Chen, Wang, and their partners made sense of in their paper. “Then, we treat the outer layer of the perovskite film with trifluorocarbon-changed phenethylammonium iodide (2CF3-PEAI) to improve the energy levels, passivate deserts, and safeguard the film against dampness.”
Chen, Wang, and their partners applied their methodology to a FAPbI3 film, which they then used to make rearranged PSCs. They assessed these sun-oriented cells in a progression of tests and found that they performed strikingly well, both in terms of strength and energy productivity.
In their paper, the team stated, “The inverted PSCs simultaneously achieve improved stability and 25.1% efficiency (24.5% from the reverse current-voltage scan measured by a third-party institution).” The gadgets kept up with 97.4% and 98.2% of their underlying power change efficiencies subsequent to working under persistent 1-sun air mass 1.5 G light for 1,800 h and under clammy intensity conditions (85°C and 85% relative dampness) for 1,000 h, separately.”
In order to create inverted PSCs that are both more stable and efficient in the future, the approach that Chen, Wang, and their colleagues came up with could be modified and applied by other research teams. While the group explicitly applied the DBSO-added substance and 2CF3-PEAI covering to FAPbI3 films, their methodology might actually additionally assist with diminishing imperfections and working on the exhibition of other perovskite materials.
More information: Rui Chen et al, Reduction of bulk and surface defects in inverted methylammonium- and bromide-free formamidinium perovskite solar cells, Nature Energy (2023). DOI: 10.1038/s41560-023-01288-7
