The underlying hole-transfer mechanism in high-efficiency OSC bulk heterojunctions based on acceptor-donor-acceptor (A-D-A) nonfullerene acceptors (NFAs) remains unclear. Herein, we study the hole-transfer process between copolymer donor J91 and five A-D-A NFAs with different highest occupied molecular orbital energy offsets (Δ) (0.05-0.42 eV) via ultrafast optical spectroscopies. Transient absorption spectra reveal a rapid hole-transfer rate with small Δ, suggesting that a large energy offset is not required to overcome the exciton binding energy. Capacitance-frequency spectra and time-resolved photoluminescence spectra confirm the delocalization of an A-D-A-structured acceptor exciton with weak binding energy. Relative to the hole-transfer rate, hole-transfer efficiency is the key factor affecting device performance. We propose that holes primarily stem from weakly bound acceptor exciton dissociation, revealing a new insight into the hole-transfer process in A-D-A NFA-based OSCs.
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http://dx.doi.org/10.1021/acs.jpclett.9b02837 | DOI Listing |
ACS Earth Space Chem
December 2024
School of Chemistry, University of Leeds, Leeds LS2 9JT, U.K.
Rate coefficients for the reaction of CH with CHO were measured for the first time over the temperature range of 37-603 K, with the CH radicals produced by pulsed laser photolysis and detected by CH radical chemiluminescence following their reaction with O. The low temperature measurements (≤93 K) relevant to the interstellar medium were made within a Laval nozzle gas expansion, while higher temperature measurements (≥308 K) were made within a temperature controlled reaction cell. The rate coefficients display a negative temperature dependence below 300 K, reaching (1.
View Article and Find Full Text PDFNanoscale
December 2024
Optoelectronics and Photonics Laboratory, Department of Physics, Tezpur University, Napaam 784028, Assam, India.
SnS holds great promise in optoelectronics, especially in photovoltaic devices, due to its exceptional intrinsic electronic properties and optimal optical absorption. However, its prospective applications are often limited by structural instability or oxidation, leading to internal or external defect states. This study proposes a mixed-phase SnS/h-BN heterostructure to enhance chemical and thermal stability while preserving the intrinsic optoelectronic properties of SnS.
View Article and Find Full Text PDFFood Chem
December 2024
College of Food Engineering, Harbin University of Commerce, 150028 Harbin, China. Electronic address:
To improve the toughness of the rice dough, protein transglutaminase (TGase) combined with sodium metabisulfite (SMB) modification was used. The influences of modification on rice dough and protein were investigated, and their physicochemical and structural characteristics were analyzed. Mechanical analysis results indicated that the tanδ and texture characteristics of the modified rice dough were close to those of the wheat dough.
View Article and Find Full Text PDFInt J Mol Sci
December 2024
Research Center of Biotechnology, A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, Moscow 119071, Russia.
Pediatric dilated cardiomyopathy (DCM) is a rare heart muscle disorder leading to the enlargement of all chambers and systolic dysfunction. We identified a novel de novo variant, c.88A>G (p.
View Article and Find Full Text PDFMolecules
November 2024
Department of Chemistry, Technical University of Denmark, Kemitorvet 206, 2800 Kongens Lyngby, Denmark.
A recent broadband rotational spectroscopic investigation of the cross-association mechanisms of CO with monoethanolamine (MEA) in molecular beams [F. Xie et al., , , , e202218539] revealed an intriguing affinity of CO to the hydroxy group.
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