Isolation and Characterization of the Unexpected 1- n-Octyloxyperopyrene: A Solution-Processable p-Type Organic Semiconductor.

The synthesis and optical, electrochemical, thermal, and electrical characterization of a new and unexpected 1- n-octyloxyperopyrene is reported. The structure of 1- n-octyloxyperopyrene has been unambiguously established by single-crystal X-ray diffraction. The solubility of this polycyclic aromatic hydrocarbon, endowed by the alkoxy substituent, allows the fabrication of thin-film field-effect transistors by liquid deposition methods. These devices show hole mobilities up to 1.61 × 10-3 cm2 V-1 s-1.

Readily Processable Hole-Transporting Peropyrene Gels.

The development of organic electronics requires scalable solution-processing methods that enable the fabrication of electronic devices over large areas at low cost. The preparation of peropyrene gels constituted of 3D networks of entangled 1D ribbon-like fibrils that extend over the µm scale are now reported. OFETs were easily fabricated by depositing the gels in the sol state over bottom-gate bottom-contact transistors and by allowing its gelation thereafter. Electrical characterisation of such field-effect transistors shows a good balance between processability and performance with hole mobilities that are two orders of magnitude higher than those observed in thin films obtained from non-gelating solvents under the same conditions.

Synthesis and Properties of a Twisted and Stable Tetracyano-Substituted Tetrabenzoheptacene.

An approach for the synthesis of pyrene-fused acenes that allows the introduction of electron-withdrawing cyano groups in key positions that simultaneously (i) induce twists in the aromatic framework and (ii) stabilize the LUMO level is reported. This combination of steric and electronic features provide a twisted, stable, and n-type tetrabenzoheptacene as confirmed by a combination of theoretical calculations and optical, electrochemical, thermal, and electrical characterization.

Enhancement of the Performance of Perovskite Solar Cells, LEDs, and Optical Amplifiers by Anti-Solvent Additive Deposition.

The efficiency of perovskite optoelectronic devices is increased by a novel method; its suitability for perovskite solar cells, light-emitting diodes, and optical amplifiers is demonstrated. The method is based on the introduction of organic additives during the anti-solvent step in the perovskite thin-film deposition process. Additives passivate grain boundaries reducing non-radiative recombination. The method can be easily extended to other additives.

K-Conjugated Dibenzoazahexacenes.

The synthesis and properties of two highly stable K-conjugated dibenzoazahexacenes are reported. Single-crystal X-ray, optoelectronic, and electrochemical characterization combined with theoretical studies show a favorable molecular packing and an optimal energy alignment of their frontier orbitals for charge transport. Electrical characterization illustrates that the preferential transport of holes or electrons depends on the number of N atoms in the aromatic framework.