Among various types of perovskite‐based tandem solar cells (TSCs), all‐perovskite TSCs are of particular attractiveness for building‐ and vehicle‐integrated photovoltaics, or space energy areas as they can be fabricated on flexible and lightweight substrates with a very high power‐to‐weight ratio. However, the efficiency of flexible all‐perovskite tandems is lagging far behind their rigid counterparts primarily due to the challenges in developing efficient wide‐bandgap (WBG) perovskite solar cells on the flexible substrates as well as their low open‐circuit voltage (VOC). Here, it is reported that the use of self‐assembled monolayers as hole‐selective contact effectively suppresses the interfacial recombination and allows the subsequent uniform growth of a 1.77 eV WBG perovskite with superior optoelectronic quality. In addition, a postdeposition treatment with 2‐thiopheneethylammonium chloride is employed to further suppress the bulk and interfacial recombination, boosting the VOC of the WBG top cell to 1.29 V. Based on this, the first proof‐of‐concept four‐terminal all‐perovskite flexible TSC with a power conversion efficiency of 22.6% is presented. When integrating into two‐terminal flexible tandems, 23.8% flexible all‐perovskite TSCs with a superior VOC of 2.1 V is achieved, which is on par with the VOC reported on the 28% all‐perovskite tandems grown on the rigid substrate.
Tin fluoride (SnF 2 ) is an indispensable additive for high-efficiency Pb-Sn perovskite solar cells (PSCs). However, the spatial distribution of SnF 2 in the perovskite absorber is seldom investigated while essential for a comprehensive understanding of the exact role of the SnF 2 additive. Herein, we revealed the spatial distribution of the SnF 2 additive and made structure-optoelectronic properties-flexible photovoltaic performance correlation. We observed the chemical transformation of SnF 2 to a fluorinated oxyphase on the Pb-Sn perovskite film surface due to its rapid oxidation. In addition, at the buried perovskite interface, we detected and visualized the accumulation of F − ions. We found that the photoluminescence quantum yield of Pb-Sn perovskite reached the highest value with 10 mol % SnF 2 in the precursor solution. When integrating the optimized absorber in flexible devices, we obtained the flexible Pb-Sn perovskite narrow bandgap (1.24 eV) solar cells with an efficiency of 18.5% and demonstrated 23.1% efficient flexible four-terminal all-perovskite tandem cells.
Perovskite Solar Cells
In article number 2202438, Cong Chen, Dewei Zhao, Fan Fu, and co‐workers report 15.1% flexible near‐infrared transparent wide‐bandgap (1.77 eV) perovskite solar cells with a low open‐circuit voltage–deficit of 480 mV. When paired with flexible, narrow‐bandgap (1.24 eV) perovskite solar cells, they demonstrate a 23.8% flexible all‐perovskite tandem solar cell with a superior open‐circuit voltage of 2.1 V.
Perovskite‐Cu(In,Ga)Se2 (CIGS) thin‐film tandem technology provides an exciting prospect to achieve low‐cost high‐efficiency photovoltaic devices by high throughput roll‐to‐roll processing on flexible substrates. However, no report on flexible perovskite‐CIGS mini‐modules has been published due to scribing‐related challenges in realizing near‐infrared (NIR)‐transparent perovskite mini‐modules on flexible substrates. Herein, an NIR‐transparent flexible perovskite mini‐module with an efficiency of 10.8% and an NIR‐transparency of over 75% is reported. All‐laser scribed interconnection approach is used to realize monolithic interconnection of mini‐modules on thermally sensitive soft flexible substrate. An analytical method is utilized to optimize the mini‐module layout and achieve a geometric fill factor of over 93%. Further, as a proof of concept, a flexible perovskite‐CIGS tandem mini‐module with an efficiency of 18.4% on an aperture area of 2.03 cm2 is demonstrated. To conclude, pathways for improving the efficiency of flexible NIR‐transparent perovskite mini‐modules are discussed.
This paper proposes a novel optimal Energy Management System (EMS) algorithm for Electric Vehicle (EV) charging in smart electric railway stations with renewable generation. As opposed to previous railway EMS methods, the proposed EMS coordinates the combined Regenerative Braking Energy (RBE), renewable generation, electric railway demand and EV charging demand at the EV parking lot of the railway station. Numerical results using a scenario-based approach on an actual railway station in Chur, Switzerland demonstrate that the proposed algorithm can effectively minimize the expected daily operating cost for the train station over an entire year.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.