Control of the molecular orientation of regioregular poly(3-alkylthiophene)s (RR-P3ATs) improves the performance of field-effect transistors and organic photovoltaic devices (OPVs). However, most thiophene ring planes of the RR-P3AT molecules (except RR-poly(3-butylthiophene)) in films formed by the conventional spin-coating method stand on the substrate, that is, edge-on orientation. Orientation control of RR-poly(3-dodecylthiophene) (RR-P3DDT) molecules in films formed by the friction transfer method is reported and the performance of OPVs based on friction-transferred RR-P3DDT films is compared to that of OPVs based on spin-coated films. The films are investigated by polarized ultraviolet-visible light absorption spectroscopy, Fourier transform infrared spectroscopy, and grazing-incidence X-ray diffraction measurement. For friction-transferred films, the RR-P3DDT molecular chain is uniaxially aligned parallel to the substrate plane. In addition, the thiophene ring planes of the RR-P3DDT molecules are also oriented parallel to the substrate plane, that is, face-on orientation. The power conversion efficiency (PCE) and fill factor of the RR-P3DDT/C 60 bilayer OPVs based on the friction-transferred RR-P3DDT films are higher than those of devices based on spin-coated films. The PCE and photocurrent of the device based on the friction-transferred film are larger under irradiation with polarized light parallel to the RR-P3DDT molecular chain direction than with polarized light orthogonal to the chain direction. V C 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40136.

Monodispersed Au nanoparticles composed of only 14 atoms were synthesized by a dendrimer-based template method. A spin-coated dendrimer film containing these Au nanoparticles exhibited significant resistive switching functions during the reversible scan of an applied bias.Resistive switching random access memories (RRAM), 1 including memristors, 2 classified as the forth electronic device element have attracted significant attention because they can be used as low-power memory devices. Metalinsulatormetalsandwiched nanostructures involving limited metal ion mobility 3 form the typical architecture. Meanwhile, other structures based on organic complexes, 4 metalorganic complexes, 5 and relatively large metal nanoparticles 6 were recently found to exhibit similar resistive switching behaviors. Metal nanoparticles are especially one of the promising candidates for this application in terms of the continuous and adjustable electronic properties along with the particle-size variation. Those prepared from conventional solvothermal or gas-phase methods have substantial statistical size distribution because the particle nucleations were controlled under stochastic conditions. In contrast, we have developed a template method using a dendrimer-based molecular reactor, allowing the precise size and atomicity control of metal subnanoparticles at the one-atom level.7,8 A significant advantage using the dendrimer template is very narrow size distribution based on the stoichiometrically controlled preprogrammed 9 metal-assembling complexes through a stepwise complexation process. Such narrow distribution may provide sensitive and multistep electrochemical responses, which are the most important factors for memory devices.We now report the first synthesis of well-size-controlled gold nanoparticles using a phenylazomethine dendrimer with four generations (DPAG4, Figure 1) and their application to resistive switching memory. DPAG4 was synthesized as previously reported.DPAG4 can assemble AuCl 3 through a stepwise complexation process. To a 5.15¯mol L ¹1 solution of DPAG4 in a mixed solvent (chloroform/acetonitrile = 1/1), small portions of 3.69 mmol L ¹1 AuCl 3 solution in acetonitrile were repeatedly added and equilibrated. Upon each addition, UVvis absorption spectrum was measured. Similar to those in the previous studies, 10 four independent isosbestic points appeared in turns ( Figure S1 11 ). The equimolar amount of AuCl 3 required to shift the isosbestic point was in good agreement with the number of coordination sites on each layer (generation). It is the typical behavior of a stepwise complexation from the innermost to the outermost layers. Assuming this complexation manner, we can specify the number of AuCl 3 molecules assembled in one