Two kinds of fluoroalkyl-modified naphthodithiophene diimides (NDTI) were designed and synthesized. α-Modified NDTI could form favorable slipped one-dimensional (1D) stacking and N-modified NDTI shows a torsion cofacial stacking. Single-crystal transistors confirm that both fluoroalkyl-modified NDTI possess good electron transport ability with electron mobilities of 0.065 cm2 V−1 s−1 and 1.59 cm2 V−1 s−1, respectively.

AbstractTwo different lengths of twistacenes, namely hexatwistacene and decatwistacene, induced by steric hindrance between imide groups and neighboring annulated benzene rings, were synthesized by bottom-up synthesis of palladium-catalyzed Suzuki cross-coupling and C−H activation. Single-crystal X-ray analyses revealed that decatwistacene, which is the longest twistacene reported, exhibits an astonishing overall end-to-end torsion angle of about 170°, the largest torsion angle reported. Both twistacenes have an enhanced solubility and stability with respect to light and oxygen owing to their large twisting deformations together with much lower LUMO levels caused by the introduction of imide groups, opening a window to the narrowest chiral graphene nanoribbons with good stability and processability.

AbstractTwo different lengths of twistacenes, namely hexatwistacene and decatwistacene, induced by steric hindrance between imide groups and neighboring annulated benzene rings, were synthesized by bottom-up synthesis of palladium-catalyzed Suzuki cross-coupling and C−H activation. Single-crystal X-ray analyses revealed that decatwistacene, which is the longest twistacene reported, exhibits an astonishing overall end-to-end torsion angle of about 170°, the largest torsion angle reported. Both twistacenes have an enhanced solubility and stability with respect to light and oxygen owing to their large twisting deformations together with much lower LUMO levels caused by the introduction of imide groups, opening a window to the narrowest chiral graphene nanoribbons with good stability and processability.

Two kinds of conjugated C3-symmetric perylene dyes, namely, triperylene hexaimides (TPH) and selenium-annulated triperylene hexaimides (TPH-Se), are efficiently synthesized. Both TPH and TPH-Se have broad and strong absorption in the region 300–600 nm together with suitable LUMO levels of about −3.8 eV. Single-crystal X-ray diffraction studies show that TPH displays an extremely twisted three-bladed propeller configuration and a unique 3D network assembly in which three PBI subunits in one TPH molecule have strong π–π intermolecular interactions with PBI subunits in neighboring molecules. The integration of selenophene to TPH endows TPH-Se with a more distorted propeller configuration and a more compact 3D network assembly due to the Se···O interactions. A single-crystal transistor confirms that both TPH and TPH-Se possess good electron-transport ability. TPH and TPH-Se acceptor-based solar cells show high power conversion efficiency of 8.28% and 9.28%, respectively, which mainly results from the combined properties of broad and strong absorption ability, appropriate LUMO level, desirable aggregation, high electron mobility, and good film morphology with the polymer donor.

A novel ladder-type pyrrole-fused dibenzo[a,e]pentalene, in which two benzo[a,e]pentalene units are held coplanar by a nitrogen bridge, is synthesized via double intermolecular Pd-catalyzed cascade crossover annulations. The introduction of a nitrogen bridge not only has a substantial influence on the optoelectronic properties but also improves the processability and stability.

A series of novel metal-free organic sensitizers based on N-annulated perylene derivatives have been designed and synthesized, and exhibit broad absorption spectra in the visible region. The dye-sensitized solar cells exhibit overall conversion efficiencies ranging from 4.90% to 8.28% under AM 1.5 solar conditions.

Organic single crystal transistors based on two kinds of core-tetrachlorinated perylene diimides (4ClPDIs) are fabricated. Compared with alkyl substituted 4ClPDI, the transistors based on fluoroalkyl substituted 4ClPDI exhibit an air-stable electron mobility of up to 1.43 cm2 V−1 s−1 and high photocurrent with an on/off ratio of 1000, which are associated with its close packing arrangement.

Laminated nanotapes were fabricated via conformation specific self-assembly of two N-annulated perylene derivatives (NPDs). The assemblies in solvated states were characterized using cryogenic transmission electron microscopy (cryo-TEM), and their nanostructures were modulated by the synergistic interactions of π–π stacking and hydrogen bonds.

Laterally extended naphthalene diimides composed of naphthobisbenzothiophene skeleton and two imide groups were synthesized, which exhibit interesting packing arrangements and optoelectrical properties.

A series of heterocyclic acene diimides were synthesized effectively based on the condensation of o-phenylenediamine, 1,2-benzenedithiol, and 2-aminothiophenol with 2,3,6,7-tetrabromo-1,4,5,8-naphthalene tetracarboxylic diimide. The diimides exhibit interesting optical and electrical properties with one of them showing a hole mobility up to 0.02 cm2 V–1 s–1.

Hybrid rylene arrays have been prepared via a combination of Stille coupling and C–H transformation. The ability to extend the π system along the equatorial axis of rylenes not only leads to broadened light absorption but also increases the electron affinity, which can facilitate electron injection and transport with ambient stability.

Tetracene tetracarboxylic diimides have been synthesized based on direct double ring extension of electron-deficient naphthalene diimides involving metallacyclopentadienes. Atomic structure and electronic transitions responsible for their NIR absorption spectra are investigated with quantum-chemical calculations. In light of their unique structure and admirable photophysical and electronic properties, this new molecular skeleton is promising candidate for n-type semiconductors.

A series of novel metal-free organic sensitizers based on N-annulated perylene derivatives have been designed and synthesized, and exhibit broad absorption spectra in the visible region. The dye-sensitized solar cells exhibit overall conversion efficiencies ranging from 4.90% to 8.28% under AM 1.5 solar conditions.

A novel ladder-type pyrrole-fused dibenzo[a,e]pentalene, in which two benzo[a,e]pentalene units are held coplanar by a nitrogen bridge, is synthesized via double intermolecular Pd-catalyzed cascade crossover annulations. The introduction of a nitrogen bridge not only has a substantial influence on the optoelectronic properties but also improves the processability and stability.

Laminated nanotapes were fabricated via conformation specific self-assembly of two N-annulated perylene derivatives (NPDs). The assemblies in solvated states were characterized using cryogenic transmission electron microscopy (cryo-TEM), and their nanostructures were modulated by the synergistic interactions of π–π stacking and hydrogen bonds.

Organic single crystal transistors based on two kinds of core-tetrachlorinated perylene diimides (4ClPDIs) are fabricated. Compared with alkyl substituted 4ClPDI, the transistors based on fluoroalkyl substituted 4ClPDI exhibit an air-stable electron mobility of up to 1.43 cm2 V−1 s−1 and high photocurrent with an on/off ratio of 1000, which are associated with its close packing arrangement.

Two kinds of fluoroalkyl-modified naphthodithiophene diimides (NDTI) were designed and synthesized. α-Modified NDTI could form favorable slipped one-dimensional (1D) stacking and N-modified NDTI shows a torsion cofacial stacking. Single-crystal transistors confirm that both fluoroalkyl-modified NDTI possess good electron transport ability with electron mobilities of 0.065 cm2 V−1 s−1 and 1.59 cm2 V−1 s−1, respectively.

A high performance three-dimensional (3D) thiophene-annulated perylene dye, namely tetra-PBI-S, was designed and synthesized. The appropriate LUMO level, balanced carrier mobilities and favourable phase separation make tetra-PBI-S based solar cells show a much higher power conversion efficiency (PCE) of 6.2% than tetra-PBI based solar cells with a PCE of 3.6%.

Two new polycyclic aromatic hydrocarbons with orthogonal imide groups have been synthesized and characterized. These semiconductors have strong electron affinities with an electron mobility of up to 1.75 cm2 V−1 s−1 in solution-processed single-crystalline microfibers.