The development of medium-bandgap solar cell absorber materials is of interest for the design of devices such as tandem solar cells and building-integrated photovoltaics. The recently developed perovskite solar cells can be suitable candidates for these applications. At present, wide bandgap alkylammonium lead bromide perovskite absorbers require a high-temperature sintered mesoporous TiO2 photoanode in order to function efficiently, which makes them unsuitable for some of the above applications. Here, we present for the first time highly efficient wide bandgap planar heterojunction solar cells based on the structurally related formamidinium lead bromide. We show that this material exhibits much longer diffusion lengths of the photoexcited species than its methylammonium counterpart. This results in planar heterojunction solar cells exhibiting power conversion efficiencies approaching 7%. Hence, formamidinium lead bromide is a strong candidate as a wide bandgap absorber in perovskite solar cells.
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http://dx.doi.org/10.1021/jz501237m | DOI Listing |
J Am Chem Soc
January 2025
College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing 314001, China.
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View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
i-Lab & Printable Electronics Research Center, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences(CAS), Suzhou, 215123, P. R. China.
The conductivity of AgNWs electrodes can be enhanced by incorporating Ag grids, thereby facilitating the development of large-area flexible organic solar cells (FOSCs). Ag grids from vacuum evaporation offer the advantages of simple film formation, adjustable thickness, and unique structure. However, the complex 3D multi-component structure of AgNWs electrodes will exacerbate the aggregation of large Ag particles, causing the device short circuits.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
Department of Chemistry and Centre for Processable Electronics, Imperial College London, London, W12 0BZ, UK.
Most current highly efficient organic solar cells utilize small molecules like Y6 and its derivatives as electron acceptors in the photoactive layer. In this work, a small molecule acceptor, SC8-IT4F, is developed through outer side chain engineering on the terminal thiophene of a conjugated 6,12-dihydro-dithienoindeno[2,3-d:2',3'-d']-s-indaceno[1,2-b:5,6-b']dithiophene (IDTT) central core. Compared to the reference molecule C8-IT4F, which lacks outer side chains, SC8-IT4F displays notable differences in molecule geometry (as shown by simulations), thermal behavior, single-crystal packing, and film morphology.
View Article and Find Full Text PDFAdv Mater
January 2025
Key Lab of Artificial Micro- and Nano-Structures of Ministry of Education of China, School of Physics and Technology, Wuhan University, Wuhan, 430072, China.
Porous lead iodide (PbI) film is crucial for the complete reaction between PbI and ammonium salts in sequential-deposition technology so as to achieve high crystallinity perovskite film. Herein, it is found that the tensile stress in tin (IV) oxide (SnO) electron transport layer (ETL) is a key factor influencing the morphology and crystallization of PbI films. Focusing on this, lithium trifluoromethanesulfonate (LiOTf) is used as an interfacial modifier in the SnO/PbI interface to decrease the tensile stress to reduce the necessary critical Gibbs free energy for PbI nuclei formation.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Institute of Advanced Materials (INAM), Universitat Jaume I, Av. Vicent Sos Baynat, s/n, 12071 Castellón de la Plana, Spain.
High defect concentrations at the interfaces are the basis of charge extraction losses and instability in perovskite solar cells. Surface engineering with organic cations is a common practice to solve this issue. However, the full implications of the counteranions of these cations for device functioning are often neglected.
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