Organic solar cells with an electron donor diluted in a fullerene matrix have a reduced density of donor-fullerene contacts, resulting in decreased free-carrier recombination and increased open-circuit voltages. However, the low donor concentration prevents the formation of percolation pathways for holes. Notwithstanding, high (>75%) external quantum efficiencies can be reached, suggesting an effective hole-transport mechanism. Here, we perform a systematic study of the hole mobilities of 18 donors, diluted at ∼6 mol % in C, with varying frontier energy level offsets and relaxation energies. We find that hole transport between isolated donor molecules occurs by long-range tunneling through several fullerene molecules, with the hole mobilities being correlated to the relaxation energy of the donor. The transport mechanism presented in this study is of general relevance to bulk heterojunction organic solar cells where mixed phases of fullerene containing a small fraction of a donor material or vice versa are present as well.
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http://dx.doi.org/10.1021/acs.jpclett.8b02177 | DOI Listing |
ACS Omega
December 2024
Department of Chemistry and Materials Science, Xi'an Jiaotong-Liverpool University, Suzhou, Jiangsu 215000, P. R. China.
Spiro architectures with π-conjugation have improved thermal stability and stronger photosensitivity, making them potentially useful for organic optoelectronic devices. Our recent work has demonstrated the synthetic chemistry of a novel thiophene oligomer combining 2,7-dihydrooxepine and dispiro structure and derived it into A-D-A-type compounds. The optical spectroscopy and electrochemical characteristics were investigated.
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January 2025
Dalian National Laboratory for Clean Energy, iChEM, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, P. R. China.
Organic-inorganic formamidinium lead triiodide (FAPbI) hybrid perovskite quantum dots (QDs) have garnered considerable attention in the photovoltaic field due to their narrow bandgap, exceptional environmental stability, and prolonged carrier lifetime. Unfortunately, their insulating ligands and surface vacancy defects pose significant obstacles to efficient charge transfer across device interfaces. In this work, an electrostatic harmonization strategy at the interface using a donor-acceptor dipole molecular attachment to achieve enhanced charge separation capabilities on the QD surface is ventured.
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January 2025
Department of Physics, Pukyong National University, Busan, 48513, Republic of Korea.
Improving the interface characteristics between the hole-transport layer (HTL) and perovskite absorber layer is crucial for achieving maximum efficiency in inverted perovskite solar cells (PSCs). This paper presents an effective functional compensation layer (FCL) composed of benzothiophene derivatives, particularly 5-(trifluoromethyl)-1-benzothiophene-2-carboxylic acid (TFMBTA); this layer is introduced between the MeO-2PACz HTL and perovskite absorber layer to improve the interfacial characteristics between them. This FCL improves charge transfer, hole extraction, and perovskite deposition by improving the surface morphology of the HTL and optimizing the energy level alignment.
View Article and Find Full Text PDFWater Res
December 2024
Department of Civil, Construction, and Environmental Engineering, San Diego State University, San Diego, CA 92182, USA. Electronic address:
Tire tread particles are microplastics (< 5 mm) and leach organic chemicals into aquatic environments. It is important to understand the behavior of tire wear compounds in sunlight-exposed waters in terms of their persistence, removal, and transformation. Therefore, we conducted photolysis experiments with leachates from laboratory-generated tire tread particles (TTP) over 72 h in a solar simulator to evaluate the behavior of leached compounds and fluorescent components over time.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
January 2025
Nano Photocatalysis Lab., Department of Chemistry, College of Science, Shiraz University, Shiraz, 7194684795, I.R. of Iran.
Due to the industry's rapid growth, the presence of organic pollutants, especially antibiotics, in water and wastewater resources is the main concern for wildlife and human health. Therefore, these days, a significant challenge is developing an efficient, sustainable, and eco-friendly photocatalyst. Natural biological models have numerous advantages compared to artificial model materials.
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