15 research outputs found
Cadmium burden and the risk and phenotype of prostate cancer
© 2009 Chen et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens
Improvement of the Dimensional Stability of Powder Injection Molded Compacts by Adding Swelling Inhibitor into the Debinding Solvent
Relationship between curing temperature and low stress mechanical properties of titanium dioxide catalyzed flame retardant finished cotton fabric
Functional role of extracellular signal-regulated kinase activation and c-Jun induction in phorbol ester-induced promoter activation of human 12(S)-lipoxygenase gene
Electronic and photophysical properties of the bend D-T-A-T-D derivatives for small-molecule organic photovoltaic (SM-OPV) solar cells: a DFT and TD-DFT investigation
[[abstract]]A series of D-T-A-T-D derivatives (D, electron-donating moiety; T, Ï€-conjugated linker; A, electron-acceptor moiety) with seven electron donor moieties and various electron abilities are designed to investigate the influence of the donor on photophysical properties for small-molecule organic photovoltaic solar cells. The 4,8-dimethoxybenzodithiophene (D), triphenyldsramine (D), 4-methoxy- N-(4-methoxyphenyl)- N-phenylaniline (D), 9,9-dimethyl-9H-fluorene (D), 9-methyl-9H-carbazole (D), 4-methyl-4H-dithieno-pyrrole (D), and 4,4-dimethyl-4H-cyclopenta-dithiophene (D) are adopted as the electron donor moiety. The BDTC (buta-1,3-diene-1,1,4,4-tetracarbonitrile) is used for the A moiety, and the thiophene (T) is used for the Ï€-conjugated linker. The optimized structure of D-T-A-T-D derivatives exhibits the bend molecular conformation due to the steric effect within the A moiety. The highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies of these derivatives are dependent on the electron donating ability of D, which influences the open-circuit voltage and driving force. Reorganization energy suggests that these derivatives are good hole-transporting type materials. Projected density of state analysis demonstrates that in the HOMO, the electron density distribution is delocalized on the terminal D and T moieties, while in the LUMO, the electron density distribution is localized mainly on the A moiety. The maximum absorption peak, which has relatively high light harvesting efficiency, is due to the Ï€ to Ï€* transition and can be tuned by the electron-donating ability and the resonance energy of the D moiety. The bend D-T-A-T-D/D-T-A-T-D derivatives with D moiety of 4-methyl-4H-dithieno-pyrrole (D) and 4,4-dimethyl-4H-cyclopenta-dithiophene (D) are good candidates as electron donor materials for SM-OPV.[[notice]]補æ£å®Œ