Catalytic Acceptorless Dehydrogenation (CAD) of Secondary Benzylic Alcohols into Value-Added Ketones Using Pd(II)-NHC Complexes.

For the creation of adaptable carbonyl compounds in organic synthesis, the oxidation of alcohols is a crucial step. As a sustainable alternative to the harmful traditional oxidation processes, transition-metal catalysts have recently attracted a lot of interest in acceptorless dehydrogenation reactions of alcohols. Here, using well-defined, air-stable palladium(II)-NHC catalysts (A-F), we demonstrate an effective method for the catalytic acceptorless dehydrogenation (CAD) reaction of secondary benzylic alcohols to produce the corresponding ketones and molecular hydrogen (H2). Catalytic acceptorless dehydrogenation (CAD) has been successfully used to convert a variety of alcohols, including electron-rich/electron-poor aromatic secondary alcohols, heteroaromatic secondary alcohols, and aliphatic cyclic alcohols, into their corresponding value-added ketones while only releasing molecular hydrogen as a byproduct.

A single-source precursor approach to solution processed indium arsenide thin films.

This paper reports the synthesis of the novel single-source precursor, [{(MeInAs t Bu)3}2(Me2InAs( t Bu)H)2] and the subsequent first report of aerosol-assisted chemical vapour deposition of InAs thin films. Owing to the use of the single-source precursor, highly crystalline and stoichiometric films were grown at a relatively low deposition temperature of 450 °C. Core level XPS depth profiling studies showed some partial oxidation of the film surface, however this was self-limiting and disappeared on etch profiles. Valence band XPS analysis matched well with the simulated density of state spectrum. Hall effect measurements performed on the films showed that the films were n-type with promising resistivity (3.6 × 10-3 Ω cm) and carrier mobility (410 cm2 V-1 s-1) values despite growth on amorphous glass substrates.

Bismuth oxyhalides: synthesis, structure and photoelectrochemical activity.

We report the synthesis and photoelectrochemical assessment of phase pure tetragonal matlockite structured BiOX (where X = Cl, Br, I) films. The materials were deposited using aerosol-assisted chemical vapour deposition. The measured optical bandgaps of the oxyhalides, supported by density functional theory calculations, showed a red shift with the increasing size of halide following the binding energy of the anion p-orbitals that form the valence band. Stability and photoelectrochemical studies carried out without a sacrificial electron donor showed the n-type BiOBr film to have the highest photocurrent reported for BiOBr in the literature to date (0.3 mA cm-2 at 1.23 V vs. RHE), indicating it is an excellent candidate for solar fuel production with a very low onset potential of 0.2 V vs. RHE. The high performance was attributed to the preferred growth of the film in the [011] direction, as shown by X-ray diffraction, leading to internal electric fields that minimize charge carrier recombination.

Stepwise construction of extra-large heterometallic calixarene-based cages.

Utilizing presynthesized large Na2Ni12Ln2 clusters (Ln = Dy and Tb) supported by calixarene as molecular building blocks (MBBs), we have obtained a series of cationic trigonal prismatic heterometallic organic nanocages (HMONCs) with tunable sizes through a stepwise method. Specially, in each structure of the HMONCs, three linear dicarboxylate linkers substitute the peripheral coordinated acetate ligands of two Na2Ni12Ln2 clusters to form an unprecedented Na4Ni24Ln4 HMONC through a M2L3 condensation. Moreover, magnetic study reveals that the Na2Ni12Dy2 core retains its slow magnetic relaxation behavior. Gas sorption behaviors of these HMONCs were also studied. To the best of our knowledge, these HMONCs built from large heterotrimetallic Na2Ni12Ln2 MBBs, which are based on smaller Ni4-calix ones, have not been reported in any other cages to date. In addition, this research also provides a new strategy for the design and construction of HMONCs with predictable structures and functional properties.

Correction: Self-decoration of Pt metal particles on TiO2 nanotubes used for highly efficient photocatalytic H2 production.

Correction for 'Self-decoration of Pt metal particles on TiO2 nanotubes used for highly efficient photocatalytic H2 production' by Sulaiman N. Basahel et al., Chem. Commun., 2014, 50, 6123-6125.

NH3 treatment of TiO2 nanotubes: from N-doping to semimetallic conductivity.

In the present work we show that a suitable high temperature ammonia treatment allows for the conversion of single-walled TiO2 nanotube arrays not only to a N-doped photoactive anatase material (which is already well established), but even further into fully functional titanium nitride (TiN) tubular structures that exhibit semimetallic conductivity.

Self-decoration of Pt metal particles on TiO(2) nanotubes used for highly efficient photocatalytic H(2) production.

Pt decorated TiO2 has, over the past decades, been a key material for photocatalytic hydrogen production. The present work shows that growing anodic self-organized TiO2 nanotubes from Ti-Pt alloy with a low Pt content of 0.2 at% leads to oxide nanotube layers that are self-decorated with Pt nanoparticles of 4-5 nm in diameter. The average particle spacing is in the range of ~50 nm and is partially adjustable by the anodization conditions. This intrinsic decoration of TiO2 nanotubes with Pt leads to a highly active photocatalyst for the production of H2 under UV or visible light conditions.

Combinatorial atmospheric pressure chemical vapor deposition of graded TiO2-VO2 mixed-phase composites and their dual functional property as self-cleaning and photochromic window coatings.

A combinatorial film with a phase gradient from V:TiO2 (V: Ti ≥ 0.08), through a range of TiO2-VO2 composites, to a vanadium-rich composite (V: Ti = 1.81) was grown by combinatorial atmospheric pressure chemical vapor deposition (cAPCVD). The film was grown from the reaction of TiCl4, VCl4, ethyl acetate (EtAc), and H2O at 550 °C on glass. The gradient in gas mixtures across the reactor induced compositional film growth, producing a single film with numerous phases and compositions at different positions. Seventeen unique positions distributed evenly along a central horizontal strip were investigated. The physical properties were characterized by wavelength dispersive X-ray (WDX) analysis, X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), and UV-visible spectroscopy. The functional properties examined included the degree of photoinduced hydrophilicity (PIH), UVC-photocatalysis, and thermochromism. Superhydrophilic contact angles could be achieved at all positions, even within a highly VO2-rich composite (V: Ti = 1.81). A maximum level of UVC photocatalysis was observed at a position bordering the solubility limit of V:TiO2 (V: Ti ≈ 0.21) and fragmentation into a mixed-phase composite. Within the mixed-phase TiO2: VO2 composition region (V: Ti = 1.09 to 1.81) a decrease in the semiconductor-to-metal transition temperature of VO2 from 68 to 51 °C was observed.

Implications of the crystal structure of the ammonia solvate [Au(NH3)2]Cl·4NH3.

Crystals of diammine gold(I) chloride ammonia (1/4), [Au(NH(3))(2)]Cl·4NH(3), have been grown from solutions of AuCl in liquid ammonia. The X-ray diffraction analysis (at 123 K) has shown that the crystals feature an extensive network of hydrogen bonds between the [H(3)N-Au-NH(3)](+) cations (with C(i) symmetry) and the Cl(-) anions, including also the ammonia molecules. There is no evidence for an emerging increase of the coordination number of the gold atom by adopting another ammonia molecule or by approaching a chloride anion. Moreover, the geometry of two distant and angular N-H···Au contacts is not a strong support of hydrogen bonds recently amply discussed in the literature.