Citation for published item:tmesD F vF nd edmsD gF tF nd folmD gF nd frgD hF nd gollierD F nd pri § s § i¡ D F nd qrepioniD pF nd rrrisD uF hF wF nd ryettD qF nd tonesD F nd uresD eF nd wkD tF nd winiD vF nd yrpenD eF qF nd rkinD sF F nd herouseD F gF nd teedD tF F nd ddellD hF gF @PHIPA 9wehnohemistry X opportunities for new nd lener synthesisF9D ghemil soiety reviewsFD RI @IAF ppF RIQERRUF Further information on publisher's website: Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details.

The term mesocrystal has been widely used to describe crystals that form by oriented assembly, and that exhibit nanoparticle substructures. Using calcite crystals co-precipitated with polymers as a suitable test case, this article looks critically at the concept of mesocrystals. Here we demonstrate that the data commonly used to assign mesocrystal structure may be frequently misinterpreted, and that these calcite/polymer crystals do not have nanoparticle substructures. Although morphologies suggest the presence of nanoparticles, these are only present on the crystal surface. High surface areas are only recorded for crystals freshly removed from solution and are again attributed to a thin shell of nanoparticles on a solid calcite core. Line broadening in powder X-ray diffraction spectra is due to lattice strain only, precluding the existence of a nanoparticle sub-structure. Finally, study of the formation mechanism provides no evidence for crystalline precursor particles. A re-evaluation of existing literature on some mesocrystals may therefore be required.

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A novel High-Throughput Continuous Hydrothermal (HiTCH) flow synthesis reactor was used to make directly and rapidly a 66-sample nanoparticle library (entire phase diagram) of nanocrystalline Ce(x)Zr(y)Y(z)O(2-delta) in less than 12 h. High resolution PXRD data were obtained for the entire heat-treated library (at 1000 degrees C/1 h) in less than a day using the new robotic beamline I11, located at Diamond Light Source (DLS). This allowed Rietveld-quality powder X-ray diffraction (PXRD) data collection of the entire 66-sample library in <1 day. Consequently, the authors rapidly mapped out phase behavior and sintering behaviors for the entire library. Out of the entire 66-sample heat-treated library, the PXRD data suggests that 43 possess the fluorite structure, of which 30 (out of 36) are ternary compositions. The speed, quantity and quality of data obtained by our new approach, offers an exciting new development which will allow structure-property relationships to be accessed for nanoceramics in much shorter time periods.

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This paper reports on an investigation into the formation of TiO(2) thin films, whereby X-ray diffraction is used to map systematic changes in preferred orientation and phase observed throughout the films. The key to this strategy is the recording of X-ray diffraction patterns of specific and isolated areas of a substrate, ensuring this specificity by the use of a small X-ray sample illumination area (approximately 3-5 mm(2)). A map of the variation in film composition can then be built up by recording such diffraction patterns at regular intervals over the whole substrate. Two titania films will be presented, grown using atmospheric pressure chemical vapor deposition, at 450 and 600 degrees C, from TiCl(4) and ethyl-acetate precursors. The film grown at 450 degrees C showed a systematic change in preferred orientation, while the film grown at 600 degrees C was composed of a mixture of the rutile and anatase phases of TiO(2) with the ratio of these phases altering with position on the substrate. The results of physical property measurements and electron microscopy carried out on the films are also reported, conducted at locations identified by the X-ray diffraction mapping procedure as having different compositions, and hence different physical responses. We found that the photocatalytic activity and hydrophobicity were dependent on the rutile:anatase ratio at any given location on the film.

Synergetic experimental and DFT insights of energy band structures and photogenerated reactive intermediates are indispensable to design impurity-doped photocatalysts for photocatalytic environment remediation and solar fuels. Herein, despite the larger bandgap (Eg), Zn-doped BiOBr samples exhibited superior activity to BiOBr in the photocatalytic water splitting but adverse in photodegradation of Rhodamine B under visible-light illumination. Based on the spectral and electrochemical impedance characterisations and DFT simulations, the broader bandgap of Zn-doped BiOBr was explicitly assigned to more positive valence band maximum (VBM) and more negative conduction band minimum (CBM). The enhanced photocatalytic water splitting on Zn-doped BiOBr was assigned to the higher redox chemical potentials of charge carriers on respective CBM and VBM, suppressed back reaction and reduced recombination of photogenerated charge carriers. However, the reduced e-h + recombination on Zn-doped BiOBr cannot cancel the adverse influences of its weaker light absorption and dye-sensitisation effects, leading to slower RhB photodegradation.

Aerosol assisted chemical vapor deposition (AACVD) reactions of GaMe 3 , InMe 3 , and 6 equiv of the donor functionalized alcohol, HOCH 2 CH 2 OMe, in toluene resulted in the deposition of colorless, transparent gallium-indium-oxide films at a range of temperatures (350-450 °C). The gallium-indium-oxide films were analyzed by a range of techniques including scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), glancingangle X-ray powder diffraction (XRD), and wavelength dispersive analysis of X-rays (WDX). The optimum growth temperature was found to be 450 °C, which produced transparent films with a composition of Ga 0.6 In 1.4 O 3 as determined by WDX. XPS confirmed the presence of indium, gallium, and oxygen in the films. Annealing these films at 1000 °C resulted in crystalline films, and glancing-angle powder XRD showed a gallium-substituted cubic In 2 O 3 lattice was adopted with a lattice parameter, a = 9.84 Å. AFM showed that the annealed films on quartz had a root-mean-square roughness of 94-200 nm, and the work function was measured to be 4.6 eV. The four point probe method was used to determine a sheet resistivity, R s = 83.3 Ω/square, and a low electrical resistivity value (for example 6.66 Â 10 -4 Ω cm in 80 nm sample thickness, as determined by side-on SEM for films deposited on glass).