No abstract

Herein, a simple structure, nonchlorinated solvent processable high mobility donor–acceptor conjugated polymer, poly(2,5‐bis(4‐hexyldodecyl)‐2,5‐dihydro‐3,6‐di‐2‐thienyl‐pyrrolo[3,4‐c]pyrrole‐1,4‐dione‐alt‐thiophene) (PDPPT3‐HDO), is reported. The enhanced solubility in nonchlorinated solvent is realized based on a denser alkyl side chains strategy by incorporating small size comonomer thiophene. An associated benefit of thiophene comonomer is the remarkable structural simplicity of the resulting polymer, which is advantageous for industrial scaling up. The alkyl side chain density and structure of PDPPT3‐HDO can efficiently control the self‐assembly properties in solution and film. By bar coating from o‐xylene solution, PDPPT3‐HDO forms aligned films and exhibits high hole mobility of up to 9.24 cm2 V−1 s−1 in organic thin film transistors (OTFTs). Notably, the bar‐coated OTFT based on PDPPT3‐HDO shows a close to ideal transistor model and a high mobility reliability factor of 87%. The multiple benefits of increased side chain density strategy may encourage the design of high mobility polymers that meet the requirements of mass production of OTFT materials and devices.

We report a novel solid-state molecular device structure based on double self-assembled monolayers (D-SAM) incorporated into the suspended nanowire architecture to form a “Au|SAM-1||SAM-2|Au” junction. Using commercially available thiol molecules that are devoid of synthetic difficulty, we constructed a “Au|S-(CH2)6-ferrocene||SAM-2|Au” junction with various lengths and chemical structures of SAM-2 to tune the coupling between the ferrocene conductive molecular orbital and electrode of the junction. Combining low noise and a wide temperature range measurement, we demonstrated systematically modulated conduction depending on the length and chemical nature of SAM-2. Meanwhile, the transport mechanism transition from tunneling to hopping and the intermediate state accompanied by the current fluctuation due to the coexistence of the hopping and tunneling transport channels were observed. Considering the versatility of this solid-state D-SAM in modulating the electrode–molecule interface and electroactive groups, this strategy thus provides a novel facile strategy for tailorable nanoscale charge transport studies and functional molecular devices.

Single level tunneling model has been the most popular model system in both the experimental and theoretical study of molecular junctions. We performed a detailed simulation single-level performance of the...