Highly polarized electroluminescence from a liquid‐crystal polymer device, based on a branched polyfluorene with a branched side chain, is demonstrated here as a further step towards the use of organic electroluminescent (EL) devices as backlights in conventional liquid‐crystal displays. The modification of a polyimide (PI) for hole conduction by addition of a suitable filler at moderate concentration is reported and the performance of a device containing such a rubbed, hole‐conductor‐filled PI layer as the alignment layer is compared with that of a device with a PI‐only alignment layer.

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Efficient deep‐blue electroluminescence(EL) is obtained via end‐capping polyfluorene (PF) homopolymers with hole‐transporting moieties (HTMs). Strong evidence that the observed improvement in device performance is related to the end‐capper moieties comes from the comparison of two different end‐cappers. The HTM does not disturb the liquid‐crystal properties of the PF polymer. Using doped polyimide alignment layers, polarized light‐emitting diodes (LEDs) with a polarization ratio in excess of twenty at an efficiency of 0.25 cd/A could be realized.

cyclic voltammograms were taken for these two carbons by varying the scan rate from 5 mV/s to 50 mV/s, the SNU-2 carbon kept the rectangular-shape up to a scan rate of 20 mV/s (Fig. 5b, solid line). In contrast, the MSC-25 carbon showed a deformed cyclic voltammogram at a scan rate of 10 mV/s and a completely collapsed one at a scan rate of 20 mV/s (Fig. 5b, dotted line). A detailed discussion on the electrochemical studies of the material will be presented in a forthcoming paper.In conclusion, we have made a new high surface area mesoporous carbon using Al-HMS as a template. From this research we discovered that the pores of HMS are 3D interconnected, unlike the originally proposed disordered hexagonal structure. The EDLC performance of the carbon material was superior to the commercially available carbon MSC-25 due to improved mesoporosity. The CV of the mesoporous carbon showed ideal rectangular shapes at a high scan rate of 20 mV/s.

The optical and electrical properties of 11-20 nm thick films composed of approximately 4 nm gold nanoparticles (Au-NPs) interlinked by six organic dithiol or bis-dithiocarbamate derivatives were compared to investigate how these properties depend on the core of the linker molecule (benzene or cyclohexane) and its metal-binding substituents (thiol or dithiocarbamate). Films prepared with the thiol-terminated linker molecules, (1,4-bis(mercaptomethyl)benzene, 1,4-bis(mercaptomethyl)cyclohexane, 1,4-bis(mercaptoacetamido)benzene, and 1,4-bis(mercaptoacetamido)cyclohexane), exhibit thermally activated charge transport. The activation energies lie between 59 and 71 meV. These films show distinct plasmon absorption bands with maxima between 554 and 589 nm. In contrast, the film prepared with 1,4-cyclohexane-bis(dithiocarbamate) has a significantly red-shifted plasmon band ( approximately 626 nm) and a pronounced absorbance in the near infrared. The activation energy for charge transport is only 14 meV. These differences are explained in terms of the formation of a resonant state at the interface due to overlap of the molecular orbital and metal wave function, leading to an apparent increase in NP diameter. The film prepared with 1,4-phenylene-bis(dithiocarbamate) exhibits metallic properties, indicating the full extension of the electron wave function between interlinked NPs. In all cases, the replacement of the benzene ring with a cyclohexane ring in the center of the linker molecule leads to a 1 order of magnitude decrease in conductivity. A linear relationship is obtained when the logarithm of conductivity is plotted as a function of the number of nonconjugated bonds in the linker molecules. This suggests that nonresonant tunneling along the nonconjugated parts of the molecule governs the electron tunneling decay constant (beta(N)(-)(CON)), while the contribution from the conjugated parts of the molecule is weak (corresponding to resonant tunneling). The obtained value for beta(N)(-)(CON) is approximately 1.0 (per non-conjugated bond) and independent of the nanoparticle-binding group. Hence, the molecules can be viewed as consisting of serial connections of electrically insulating (nonconjugated) and conductive (conjugated) parts.