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Spray coating, a simple and low‐cost technique for large‐scale film deposition, is employed to fabricate mesoporous titania films, which are electron‐transporting layers in all‐solid‐state dye‐sensitized solar cells (DSSCs). To optimize solar cell performance, presynthesized crystalline titania nanoparticles are introduced into the mesoporous titania films. The composite film morphology is examined with scanning electron microscopy, grazing incidence small‐angle X‐ray scattering, and nitrogen adsorption–desorption isotherms. The crystal phase and crystallite sizes are verified by X‐ray diffraction measurements. The photovoltaic performance of all‐solid‐state DSSCs is investigated. The findings reveal that an optimal active layer of the all‐solid‐state DSSC is obtained by including 50 wt% titania nanoparticles, showing a foam‐like morphology with an average pore size of 20 nm, featuring an anatase phase, and presenting a surface area of 225.2 m2 g−1. The optimized morphology obtained by adding 50 wt% presynthesized crystalline titania nanoparticles yields, correspondingly, the best solar cell efficiency of 2.7 ± 0.1%., Financial support by TUM.solar in the context of the Bavarian Collaborative Research Project “Solar Technologies Go Hybrid” (SolTech), by the GreenTech Initiative (Interface Science for Photovoltaics – ISPV) of the EuroTech Universities and by the Nanosystems Initiative Munich (NIM) is gratefully acknowledged. V.K. thanks the Bavarian State Ministry of Sciences, Research and Arts for funding this research work via project “Energy Valley Bavaria.” L.S., W.W., and Y.Y. acknowledge the China Scholarship Council (CSC).

A subsea flexible pipe containing isotropic poly(vinylidene fluoride) (PVDF) layers is subjected to rapid decompression after being put in pressurized equilibrium with a fluid containing supercritical CO2. The PVDF layers have flowed radially into gaps of adjacent metallic coils forming whitened noses. Microbeam small-angle X-Ray scattering (SAXS) scanning reveals a considerable morphological gradient in the polymer layers. PVDF layers (inner: wear, outer: barrier) in two zones (undamaged and damaged) are scanned. Far from noses and damage zone, the samples are isotropic without voids. Their morphological parameters are determined and compared to virgin material. Approaching the noses, the structure turns into highly oriented microfibrils perpendicular to the local flow into the gaps. Here, voids extend parallel to the microfibrils. At edges of the metallic structure, they turn more perpendicular to the layer. Crystallite orientation extends out to both sides of the whitened nose regions, but in the undamaged samples, tilting of the orientation direction and void-formation are restricted to the white regions: successive mechanisms of cold drawing are mapped into space. Under the damaged spot, voids and crystallite orientation extend through the entire layer. POLYM. ENG. SCI., 2015. © 2015 Society of Plastics Engineers

Microfocus X-ray scattering and micro Raman spectroscopy have been applied to study the β-transcrystalline morphology in isotactic polypropylene. The transformation from the α- to the β-form through the so-called bifurcation of growth mechanism has been investigated with high spatial resolution. We found that the mixed α-β region does not present spatial correlation along the shearing direction, implying that there is no cooperative crystallization from the different β-nucleation centres. In addition, a strong change in the lamellar orientation of the α-form thin layer that induces the growth of the β-crystallites has been observed for the first time. Finally, changes in the relative intensities of some selected Raman bands allowed the observation of the α-β transformation process at the molecular level. (© 2014 WILEY-VCH Verlag GmbH &Co. KGaA, Weinheim) In fibre-reinforced materials the interaction between the fibre and the matrix strongly affects the final properties of the material. Therefore, a detailed analysis of the interface is of utmost importance. By applying a battery of different microscopic techniques, we investigate the transcrystalline polymorphic morphology of isotactic polypropylene with unprecedented spatial resolution.

A simple, easily accessible solvent-free method for the dispersion of MWCNTs into PET is proposed, based on the preparation of a microparticulate polymer/nanotube masterbatch via cryogenic impact-milling and its subsequent melt blending with the bulk polymer. Thermal and mechanical properties of nanocomposites prepared using this method were evaluated as a function of nanotube concentration. Thermal stability was improved, and superior crystallization behavior of PET in the nanocomposites was observed. Significant improvements of around 25% in tensile strength and tensile modulus of the nanocomposites was achieved using this strategy, with only 0.25 wt.-% MWCNT, compared to previous literature data where 1wt.-% MWCNT was employed.

Solution-processed organic bulk heterojunction solar cells based on poly(3-hexylthiophene) (P3HT) blended with [6,6]-phenyl-C60-butyric acid methyl ester are doped with different concentrations of iron (II,III) oxide nanoparticles (Fe3O4). The power conversion efficiency of the devices doped at low concentrations is improved up to 11%. The improvement finds its origin in a lower recombination current, which is a consequence of an increased effective exciton lifetime according to the J–V characteristics and the optoelectronical analysis of the films. The increase in performance cannot be attributed to changes in morphology or crystallinity according to grazing-incidence X-ray scattering experiments. The evolution of the solar cell short-circuit current at low doping concentrations is related to variations in the arrangement of the crystalline regions of P3HT. For high doping concentrations (above 1.0 wt%) the performance of the solar cell decays rapidly, ascribed to the increased leakage currents in the device caused by the presence of nanoparticles.