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Organic field-effect transistors (OFETs) have attracted wide attention due to their low cost, light weight, and mechanical flexibility. However, stability limits the practical application of OFETs. Although many strategies have been developed to stabilize organic semiconductor (OSC) films to improve the stability of OFETs, the impact of the electrode on the stability of OFETs has been ignored. Here, we demonstrate in detail the influence of recrystallization of polycrystalline metal electrodes on the stability of OFETs. Furthermore, the mechanically and thermally stable nano-graphene (NG) electrodes are prepared by the plasma-enhanced chemical vapor deposition (PECVD) method. The NG electrodes show good compatibility with OSCs, and the average mobility of bottom-gate bottom-contact dinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene (DNTT) OFETs reaches 1.31 cm2 V−1 s−1. Moreover, the stable NG electrodes greatly improve the thermal stability of DNTT OFETs. This work proves that the stability of the electrodes plays a vital role in the stability of OFETs and provides a new idea for stabilizing OFETs. [ABSTRACT FROM AUTHOR]

Organic field‐effect transistors (OFETs) show great application potential in organic electronic and optoelectronic fields due to their excellent mechanical flexibility, low cost, and solution processing. However, grain boundaries (GBs) disrupt the aggregation state of organic semiconductor (OSC) films and hinder electrical performance and stability, which limits the application of OFETs. Besides, the sensitive nature of GBs is widely used in sensing, but detailed descriptions of the GBs are scarce. This review aims to fill this knowledge gap. The role of GBs and their effect on the performance and stability of OFETs are analyzed, followed by a detailed summary of the characterization of GBs. Then, strategies for suppressing the negative effects of GBs and utilizing the sensitive nature of GBs for application are proposed. Finally, potential research directions for GBs in OFETs are discussed. [ABSTRACT FROM AUTHOR]

Objective: To observe the effect of local administration of thalidomide on neointimal formation after balloon-induced carotid artery injury in rats., Methods: Forty-eight male Sprague-Dawley rats were randomly divided into 3 groups (n = 16): Sham operation group (group A), alone operation group (group B) and Thalidomide group (group C). The carotid arteries of group B and group C were injured by a conventional percutaneous transluminal coronary angioplasty (PTCA) balloon catheter. Group C was treated by local delivery of thalidomide, and group B did not receive thalidomide. The arteries of group A were not injured. Seven and 14 days after balloon injury, rats were sacrificed. Serum concentrations of vascular endothelial growth factor (VEGF) and tumor necrosis factor-α (TNF-α) were measured using enzyme-linked immunosorbent assay (ELISA). Neointima area, lumen area, macrophage infiltration and local expression of VEGF were measured using morphometric and immunohistochemical analyses. Real-time reverse transcriptase polymerase chain reaction (RT-PCR) was used to examine VEGF mRNA expression., Results: The VEGF levels were significantly increased in group B than in group C at 7 days (4.82 ± 0.17 pg/mL vs 0.98 ± 0.1 pg/mL, P < 0.01) and 14 days (6.3 ± 0.16 pg/mL vs 1.03 ± 0.09 pg/mL, P < 0.01). The TNF-α levels were also significantly increased in group B than in group C at 7 days (83 ± 1.01 pg/mL vs 76.37 ± 0.75 pg/mL, P < 0.01) and 14 days (84.06 ± 1.11 pg/mL vs 78.46 ± 0.94 pg/mL, P < 0.01). However, the area of neointimal formation was significantly reduced in group C than in group B at 14 days (0.07± 0.01 mm 2 vs 0.12± 0.04 mm 2 , P < 0.01). Macrophage infiltration and local expression of VEGF in the injured arteries were significantly reduced in group C than in group B at 14 days. VEGF mRNA expression was significantly reduced in Group C than in group B at 14 days (6.3 ± 0.16 vs 1.02 ± 0.1, P < 0.01)., Conclusions: Thalidomide, which is a specific VEGF inhibitor, significantly inhibited neointimal hyperplasia and vascular restenosis after balloon injury to the carotid artery in rats, thus potentially providing a novel method for the prevention and treatment of restenosis, especially in-stent restenosis., (Copyright © 2018. Published by Elsevier GmbH.)