With the aim of enhancing the field‐effect mobility by promoting surface‐mediated two‐dimensional molecular ordering in self‐aligned regioregular poly(3‐hexylthiophene) (P3HT) we have controlled the intermolecular interaction at the interface between P3HT and the insulator substrate by using self‐assembled monolayers (SAMs) functionalized with various groups (–NH2, –OH, and –CH3). We have found that, depending on the properties of the substrate surface, the P3HT nanocrystals adopt two different orientations—parallel and perpendicular to the insulator substrate—which have field‐effect mobilities that differ by more than a factor of 4, and that are as high as 0.28 cm2 V–1 s–1. This surprising increase in field‐effect mobility arises in particular for the perpendicular orientation of the nanocrystals with respect to the insulator substrate. Further, the perpendicular orientation of P3HT nanocrystals can be explained by the following factors: the unshared electron pairs of the SAM end groups, the π–H interactions between the thienyl‐backbone bearing π‐systems and the H (hydrogen) atoms of the SAM end groups, and interdigitation between the alkyl chains of P3HT and the alkyl chains of the SAMs.

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We have fabricated a transparent conducting double-layer metal electrode for top emission organic light-emitting devices which consists of thin layers of Ca and Ag metals of different thicknesses, deposited by the vacuum evaporation technique. The process is clean and does not damage the underlaying organic layers. High optical transparency over 70%, low reflectivity (14%) in the visible region, and low electrical sheet resistance (12 ohms/square) in Ca(10 nm)–Ag(10 nm) structures are reported. This transparent conducting Ca–Ag metal electrode opens a practical way to fabricate top-emitting organic displays without generating damage-induced states.

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composite nanospindles (CNS) are synthesized by a simple and cost effective coprecipitation method. CeO 2 /Fe 2 O 3 CNS used as an efficient recyclable photocatalyst for degrading Eosin Yellow (EY) dye under visible light irradiation possess high degradation rate of 98% after 25 min. The estimated electrical energy efficiency of CeO 2 /Fe 2 O 3 CNS shows the consumption of less energy (6.588 kWhm -3 order -1 ) in degrading EY. Besides, the CeO 2 /Fe 2 O 3 CNS exhibits a specific capacitance of 142.6 F g -1 at a scan rate of 5 mV s -1 . Moreover, the composite displays excellent capacitance retention of 94.8% after 1000 cycles. This newly designed CeO 2 /Fe 2 O 3 CNS with enhanced visible light-driven photocatalytic activity and good supercapacitive cycling stability has great potential for use as wastewater treatment and energy storage applications.