Nanostructured niobium oxide (NO) semiconductor is gaining increasing attention as electronic, optical, and electro-optic material. However, the preparation of stable NO nanofilms with reproducible morphology and behavior remains a challenge. 10Here we show a rapid, well-controlled, and efficient way to synthesize NO films with the self-organized columnlike nanostructured morphologies and advanced functional properties. The films are developed via the growth of a nanoporous anodic alumina layer, followed by the pore-directed 15 anodizing of the Nb underlayer. The columns may grow 30-150 nm wide, up to 900 nm long, with the aspect ratio up to 20, being anchored to a thin continuous oxide layer that separates the columns from the substrate. The as anodized films have a graded chemical composition changing from amorphous Nb 2 O 5 mixed with Al 2 O 3 , Si-, and P-containing species in the surface region to NbO 2 in the lower film layer. The post-anodizing treatments result in the controlled 20 formation of Nb 2 O 5 , NbO 2 , and NbO crystal phases, accompanied by transformation from nearly perfect dielectric to n-type semiconductor behavior of the films. The approach allows for the smooth film growth without early dielectric breakdown, stress-generated defects, or destructive dissolution at the respective interfaces, which is a unique situation in the oxide films on niobium. The functional properties of the NO films, revealed to date, allow for potential applications as nanocomposite capacitor dielectrics and active 25 layers for semiconductor gas microsensors with the sensitivity to ethanol and the response to hydrogen being among best ever reported.

Solvent vapour annealing (SVA), which consists of exposing the active layer of organic films to a vapour of solvent directly after deposition, has been used in small molecule bulk heterojunction (SM-BHJ) solar cell devices whose active layer consisted of 3,6-bis(5-(benzofuran-2-yl)thiophen-2-yl)-2,5-bis(2-ethylhexyl)pyrrolo [3,4-c]pyrrole-1,4-dione (DPP(TBFu) 2 ) and [6,6]-phenyl-C 71 -butyric acid methyl ester (PC 71 BM). We demonstrate that upon SVA, well-ordered crystalline domains of the DPP(TBFu) 2 donor form inside the active layer, improving greatly the Fill Factor (FF) of the devices. However, SVA treatment is always accompanied by a decrease in device short circuit current (J SC ). We demonstrate, using 1D and 2D XRD and AFM, that crystalline domains of DPP(TBFu) 2 form in a matrix of PC 71 BM acceptor. The crystallinity increases with annealing time (t a ) and the change in FF and J SC is directly linked to this. The X-ray single crystal structure of the DPP(TBFu) 2 donor was solved and provided information of the donor's packing in the solid state. The donor molecules were shown to pack in a herringbone arrangement and shown to form a highly texturized active layer film. We demonstrated that the ability of the donor to form large and highly texturized crystalline domains in the active layer is as equally as determining for the devices' characteristics as the individual stacking properties of the donor in the solid state.

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An array of highly aligned tungsten-oxide (TO) nanorods, $80 nm wide, up to 900 nm long, spatially separated at their bottoms by tungsten metal on a substrate is synthesized via the self-localized anodization of aluminum followed by the porous-alumina-assisted re-anodization of tungsten in a sputter-deposited Al/W bilayer. Moreover, the pore-directed TO nanocapsules may grow, which can be electrochemically top-opened in alumina nanopores and transformed to TO nanotubes, representing unique architectures built up on tungsten substrates to date. The as-grown nanorods are composed of amorphous WO 3 mixed with minor amounts of WO 2 and Al 2 O 3 in the outer layer and oxide-hydroxide, mainly present inside the rods. Once the growing oxide fills up the pores, it comes out as an array of exotic protuberances of highly hydrated TO, with no analogues among the other valve-metal oxides. Vacuum or air annealing at 550 C increases the portion of non-stoichiometric oxides 'doped' with OH-groups and gives monoclinic WO 2.9 or a mixture of WO 3 and WO 2.9 nanocrystalline phases, respectively. The nanorods show n-type semiconductor behavior when examined by Mott-Schottky analysis, with a high carrier density of 7 Â 10 19 or 3 Â 10 19 cm À3 for the air-or vacuum-annealed samples, associated with a charge depletion layer of about 8 or 10 nm, respectively. A model for the growth of the metal-substrate-separated TO nanocapsules and tubes is proposed and experimentally justified. The findings suggest that the new TO nanoarrays with well-defined nano-channels for carriers may form the basic elements for photoanodes or emerging 3-D micro-and nano-sensors. † Electronic supplementary information (ESI) available: Details of Mott-Schottky measurements, XRD peak quantitative analysis, structural data used from the ICSD database, rened cell parameters, crystallite size, microstrain, preferred orientation correction, and calculated wt% for each phase. See Fig. 10 (a-d) and (f) SEM images showing the growth of TO protuberances over the general surface of the alumina film and the results of their XPS surface analysis: (e) W 4f and (g) Al 2p/W 5s core-level XP surface spectra of a TO protuberance sample as imaged in (d) and (f).This journal is

Interlaboratory studies on the precision and accuracy of Rietveld quantitative phase analysis (R‐QPA) of mixtures of crystalline phases have already been carried out. However, cement‐related materials are samples of variable complexity, ranging from three phases in white Portland clinkers to more than eight phases in grey cements, that need to be specifically investigated. Here, the results are reported from a round robin on the R‐QPA of cement‐related materials from laboratories with experience in this type of analysis. The aim of the work was to evaluate the levels of precision and accuracy associated with Portland clinkers and cements. Two sets of samples have been investigated, artificial mixtures and commercial samples. Artificial mixtures were prepared by mixing (weighing) synthesized single‐crystalline phases in the appropriate proportions: (i) white clinker (Ca3SiO5, Ca2SiO4 and Ca3Al2O6) and (ii) grey cement (Ca3SiO5, Ca2SiO4, Ca3Al2O6, Ca4Al2Fe2O10, CaCO3 and CaSO4·2H2O). These two samples were used to assess the accuracy and uncertainty of the procedure, as an expected mineralogical phase fraction, the `true mineralogical percentage', is available under the assumption of negligible non‐diffracting contents. In order to assess the validity and limitations of the Rietveld‐based approach for cement materials, three commercial samples were measured: (i) white Portland clinker, (ii) grey Portland clinker and (iii) a type‐I grey Portland cement. The samples studied have been chosen in order to cover most of the different typologies of binders. Reproducibilities and general uncertainty values, with a level of confidence of 95%, are reported and discussed.