No abstract

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.

Polymeric electrophosphorescent LEDs with internal quantum efficiencies approaching unity have been fabricated. Such performance levels are previously unknown for OLEDs. The key to this success is redox chemically doped oxetane‐crosslinkable hole‐transporting layers with multilayer capability (see figure). They improve hole injection and act as electron‐blocking layers, without the need to include exciton‐ or hole‐blocking layers.

Cutting etch organic solar cells utilize the bulk‐heterojunction concept, shown in the graphic, of interpenetrating electron and hole conducting networks which enhances the exciton splitting process in the photosensitive layer. Generated charges are turned into current due to the built‐in field given by the adjoining electrodes. Here, the influence of an altered doping level of the hole collecting electrode has been investigated.

Solid electrolytes with superionic conductivity are required as a main component for all-solid-state batteries. Here we present a novel solid electrolyte with three-dimensional conducting pathways based on "lithium-rich" phosphidosilicates with ionic conductivity of σ > 10 −3 S cm −1 at room temperature and activation energy of 30-32 kJ mol −1 expanding the recently introduced family of lithium phosphidotetrelates. Aiming towards higher lithium ion conductivities systematic investigations of lithium phosphidosilicates gave access to the so far lithium-richest compound within this class of materials. The crystalline material (space group Fm3 � m), which shows reversible thermal phase transitions, can be readily obtained by ball mill synthesis from the elements followed by moderate thermal treatment of the mixture. Lithium diffusion pathways via both, tetrahedral and octahedral voids, are analyzed by temperature-dependent powder neutron diffraction measurements in combination with maximum entropy method (MEM) and DFT calculations. Moreover, the lithium ion mobility structurally indicated by a disordered Li/Si occupancy in the tetrahedral voids plus partially filled octahedral voids, is studied by temperature-dependent impedance and 7 Li NMR spectroscopy.