Evaluating the Nature of Vertical Excited-States of Fused-Ring Electron Acceptors Using TD-DFT and Density-Based Charge Transfer

2021 ◽  
Author(s):  
Weihua Tang ◽  
Amjad Ali ◽  
Muhammad Imran Rafiq ◽  
Baojing Zhou
Keyword(s):  
Solar Cells ◽  
Charge Transfer ◽  
Absorption Spectra ◽  
Excited States ◽  
Organic Solar Cells ◽  
Electron Acceptors ◽  
Electronic Transitions ◽  
Td Dft ◽  
Fused Ring ◽  
Donor Acceptor

The acceptor-donor-acceptor structured fused-ring electron acceptors (FREAs) are the utmost efficient electron acceptors used in organic solar cells (OSCs). Typically, several efficient electronic transitions contribute to the absorption spectra of...

Uphill and downhill charge generation from charge transfer to charge separated states in organic solar cells

2021 ◽  
Author(s):  
Shahidul Alam ◽  
Vojtech Nádaždy ◽  
Tomáš Váry ◽  
Christian Friebe ◽  
Rico Meitzner ◽  
...  
Keyword(s):  
Cyclic Voltammetry ◽  
Solar Cells ◽  
Charge Transfer ◽  
Energy Level ◽  
Density Of States ◽  
Organic Solar Cells ◽  
Joint Density ◽  
Charge Generation ◽  
Donor Acceptor

Energy level alignments at the organic donor–acceptor interface cannot be predicted from cyclic voltammetry. Onsets for joint density of states and charge generation, reveal cases of energy uphill and – newly observed – downhill charge generation.

Molecular Optimization of Incorporating Pyran Fused Acceptor-Donor-Acceptor Type Acceptors Enables over 15% Efficiency in Organic Solar Cells

2022 ◽  
Author(s):  
Yongsheng Chen ◽  
Simin Wu ◽  
Lingxian Meng ◽  
Zhe Zhang ◽  
Mingpeng Li ◽  
...  
Keyword(s):  
Solar Cells ◽  
Organic Solar Cells ◽  
Fused Ring ◽  
Donor Acceptor

A series of acceptor-donor-acceptor type of fused-ring non-fullerene acceptors, FOR-IN, FOR-1F and FOR-2F, were designed and synthesized, featuring with the same pyran-composed backbone and different fluorine substituted 1,1-dicyanomethylene-3-indanone terminals. The...

scholarly journals Long-lived and disorder-free charge transfer states enable endothermic charge separation in efficient non-fullerene organic solar cells

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Ture F. Hinrichsen ◽  
Christopher C. S. Chan ◽  
Chao Ma ◽  
David Paleček ◽  
Alexander Gillett ◽  
...  
Keyword(s):  
Solar Cells ◽  
Charge Transfer ◽  
Organic Solar Cells ◽  
Charge Separation ◽  
Free Charge ◽  
Charge Generation ◽  
Time Resolved ◽  
Thermodynamic Conditions ◽  
Donor Acceptor ◽  
Interfacial Charge

Abstract Organic solar cells based on non-fullerene acceptors can show high charge generation yields despite near-zero donor–acceptor energy offsets to drive charge separation and overcome the mutual Coulomb attraction between electron and hole. Here, we use time-resolved optical spectroscopy to show that free charges in these systems are generated by thermally activated dissociation of interfacial charge-transfer states that occurs over hundreds of picoseconds at room temperature, three orders of magnitude slower than comparable fullerene-based systems. Upon free electron–hole encounters at later times, both charge-transfer states and emissive excitons are regenerated, thus setting up an equilibrium between excitons, charge-transfer states and free charges. Our results suggest that the formation of long-lived and disorder-free charge-transfer states in these systems enables them to operate closely to quasi-thermodynamic conditions with no requirement for energy offsets to drive interfacial charge separation and achieve suppressed non-radiative recombination.

Isomeric effect of fluorene-based fused-ring electron acceptors to achieve high-efficiency organic solar cells

2020 ◽  
Vol 8 (10) ◽  
pp. 5315-5322 ◽  
Author(s):  
Yung-Jing Xue ◽  
Fong-Yi Cao ◽  
Po-Kai Huang ◽  
Yen-Chen Su ◽  
Yen-Ju Cheng
Keyword(s):  
Solar Cells ◽  
Organic Solar Cells ◽  
High Efficiency ◽  
Molecular Design ◽  
Electron Acceptors ◽  
Fused Ring ◽  
Isomeric Effect

A TT-terminal ladder-type donor is generally a better molecular design than the corresponding T-terminal ladder-type isomer for the development of new A–D–A NFEAs.

Replacing Cyano (−C≡N) Group to Design Environmentally Friendly Fused-ring Electron Acceptors

2021 ◽  
Author(s):  
Chuang Yao ◽  
Yezi Yang ◽  
Lei Li ◽  
Maolin Bo ◽  
Cheng Peng ◽  
...  
Keyword(s):  
Solar Cells ◽  
Power Conversion Efficiency ◽  
Conversion Efficiency ◽  
Organic Solar Cells ◽  
High Performance ◽  
Cyano Group ◽  
Power Conversion ◽  
Electron Acceptors ◽  
Fused Ring ◽  
Electron Withdrawing Group

Cyano-group (−C≡N) is an electron-withdrawing group, which has been widely used to construct high-performance fused-ring electron acceptors (FREAs). Benefiting from these FREAs, the power conversion efficiency of organic solar cells...

scholarly journals Tuning of the conformation of asymmetric nonfullerene acceptors for efficient organic solar cells

2019 ◽  
Vol 7 (39) ◽  
pp. 22279-22286 ◽  
Author(s):  
Linqiang Yang ◽  
Xin Song ◽  
Jiangsheng Yu ◽  
Hongtao Wang ◽  
Zhuohan Zhang ◽  
...  
Keyword(s):  
Solar Cells ◽  
Organic Solar Cells ◽  
Electron Acceptors ◽  
Fused Ring

In this work, three dithieno[3,2-b:2′,3′-d]pyrrol fused-ring electron acceptors (IPT-2F, IPTT-2F, and IPTTT-2F) have been successfully developed as efficient asymmetric nonfullerene acceptors (NFAs) for organic solar cells (OSCs).

An A–D–A′–D–A type small molecule acceptor with a broad absorption spectrum for organic solar cells

2018 ◽  
Vol 54 (3) ◽  
pp. 303-306 ◽  
Author(s):  
Junhui Miao ◽  
Bin Meng ◽  
Jun Liu ◽  
Lixiang Wang
Keyword(s):  
Absorption Spectrum ◽  
Solar Cells ◽  
Charge Transfer ◽  
Absorption Spectra ◽  
Small Molecule ◽  
Organic Solar Cells ◽  
Intramolecular Charge Transfer ◽  
Transfer Effect ◽  
Broad Absorption

The use of an A–D–A′–D–A strategy to develop small molecule acceptors with broad absorption spectra through suppressing the intramolecular charge transfer effect is studied.

Sign in / Sign up

Export Citation Format

Share Document