Search

Comprehensive Summary: Chlorinated conjugated polymers are rarely reported in ambipolar and n‐type organic thin‐film transistors (OTFTs), mainly due to the lack of chlorinated strong electron‐deficient building blocks. Herein, we report three new chlorine (Cl)‐ and cyano (CN)‐ substituted (E)‐1,2‐di(thiophen‐2‐yl)ethane building blocks and their copolymers P2Cl1CNTVT‐DPP, P4Cl1CNTVT‐DPP and P2Cl2CNTVT‐DPP. P2Cl1CNTVT‐DPP and P2Cl2CNTVT‐DPP had nearly planar backbone geometries, mixture of edge‐on and face‐on orientation and deeper energy levels, while P4Cl1CNTVT‐DPP had a twist backbone geometry, face‐on orientation and shallower energy levels. As a result, P2Cl1CNTVT‐DPP exhibited ambipolar characteristic with hole mobility (μh) of 0.70 cm2·V–1·s–1 and electron mobility (μe) of 0.84 cm2·V–1·s–1 and P2Cl2CNTVT‐DPP exhibited n‐type characteristic with μe of 0.64 cm2·V–1·s–1, while P4Cl1CNTVT‐DPP exhibited the lowest μe of 0.36 cm2·V–1·s–1. The devices based on P2Cl2CNTVT‐DPP exhibited good stability after being stored for 10 d in air. The results demonstrate that by rational molecular design, chlorinated polymers with low cost can be applied to high‐performance ambipolar and n‐type OTFTs. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Fabricating n‐type organic thin film transistors (OTFTs) based on small molecules via solution processing under atmospheric conditions remains challenging. Blending small molecules with polymer is an effective strategy to improve the solution processibility and air stability of the resulted devices. In this study, polystyrene was chosen to blend with n‐type small molecule DPP1012‐4F to enhance the continuity of the semiconductor layer and maintain a favorable edge‐on stacking of semiconductors. The introduction of high‐boiling point 1‐chloronaphthalene as a solvent additive in the blending system can reduce the grain boundary defects in the microscopic morphology. These changes in aggregation behavior are confirmed by X‐ray diffraction, atomic force microscopy and polarized optical microscopy analyses. Via bar‐coating of the semiconductor layers in air, the electron mobility of the resulted OTFTs under the optimal condition is 0.73 cm2·V–1·s–1, which is amongst the highest n‐type small molecule‐based OTFTs with active layers prepared in air up to now. These results show a great potential of the blending strategy in industrial roll‐to‐roll manufacture of high‐mobility n‐type OTFTs. [ABSTRACT FROM AUTHOR]

Various novel types of supramolecular nanostructures formed by nonamphiphilic azobenzene derivatives, G1 or G2 have been successfully fabricated, where G2 is structurally similar with G1 but an extra phenoxy group is connected with the azobenzene motif . Micellar structures can be obtained from the self-assembly of G1, which further transform to large-sized spindle structures; while nanorods can be initially formed by G2, which will gradually aggregate to form layered structures with much larger size. Moreover, it is found that upon addition of WP6, which can form inclusion-complex with G1 or G2, separately, the nonamphiphilic G1 and G2 thus converse to supramolecular amphiphiles WP6⊃ G1 and WP6⊃ G2, respectively. Consequently, both of the above WP6⊃ G1 and WP6⊃ G2 complexes can further assemble to form supramolecular binary vesicles, which will gradually transform to nanotubes ( WP6⊃ G1) or well-ordered nanosheets ( WP6⊃ G2). [ABSTRACT FROM AUTHOR]