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[Display omitted] • Coating stearic acid on Cu/CeO 2 improves its hydrophobicity with unchanged structure. • Stearic acid molecules are stably adsorbed with catalysts by bridging bidentate mode. • Water inhibition is greatly weakened by hydrophobic surface to improve acetone yield. Hydrophobizing the surface of catalysts is essential in many catalytic reactions confined by water, but it can be quite challenging for metal oxide catalysts because of their intricate structure and surface properties. Herein, a series of hydrophobic copper doped ceria-based catalysts was synthesized by introducing stearic acid over the surface of catalysts for the ketonization of acetic acid co-feeding with different concentration of water. Detailed investigations reveal that the stearic acid functionalization process obviously improves the hydrophobicity of Cu/CeO 2 without greatly changing their structures. Due to the excellent hydrophobicity to inhibit water in the reaction system, ketonization activities of acetic acid were greatly improved over the hydrophobic Cu/CeO 2 catalysts co-feeding with 10–65 mol.% water. Specifically, the acetic acid conversion and acetone yield reached 94 % and 87 % co-feeding with 47 % mol.% water at 330 °C over Cu/CeO 2 -2, respectively, outperforming stearic acid-free catalyst under the same conditions. Besides, the hydrophobic Cu/CeO 2 catalyst was with good durability up to 10 h on stream. The promotion of catalytic activities gives more details to help future research into the design and development of catalysts for future industrial applications of ketonization. [ABSTRACT FROM AUTHOR]

The effect of rare earth (Y, Ce, La, Sc) doping on hydrogen storage properties of Mg 2 Ni (0 1 0) surface are systematically investigated by first principles calculation. The results show that substitutional doping of Ce to Mg atoms significantly reduces the H diffusion barrier by 0.32 eV and the H 2 desorption barrier by 1.0 eV, thereby improving the hydrogen storage performance of Mg 2 Ni. [Display omitted] • The rare earth elements (Y, Ce, La, Sc) doped Mg 2 Ni (0 1 0) surface are thermodynamic feasible. • For the rare earth elements doped Mg 2 Ni (0 1 0) surface, the Ni(3d) site is the most stable doping site. • The substitution doping of Ce to Mg atom reduces the H atom diffusion barrier by 0.32 eV and H 2 desorption barrier by 1.0 eV. • Ce atom weaken the binding strength between H and Mg 2 Ni (0 1 0) substrate, thus improve the hydrogen storage properties of Mg 2 Ni. Rare earth doping has been proved to be an effective method to improve hydrogen storage properties of Mg-based alloys. In this work, the effect of rare earth (Y, Ce, La, Sc) doping on the thermal stability, electronic property and hydrogen adsorption/desorption behavior of Mg 2 Ni (0 1 0) surface are systematically investigated by first principles calculation. The results show that rare earth doping in Mg 2 Ni (0 1 0) surface are thermodynamic feasible. The calculated electronic structures shown that rare earth atoms weaken the binding strength between H and Mg 2 Ni (0 1 0) substrate, thus reduce the hydrogen diffusion and desorption energies barriers, and improve the hydrogen storage properties of Mg 2 Ni. Among the four rare earth elements, Ce shows the best potential. Notably, the substitution doping of Ce to Mg atom significantly reduces the H diffusion barrier by 0.32 eV and H 2 desorption barrier by 1.0 eV. This discovery provides a direction for the preparation of rare earth doped Mg 2 Ni hydrogen storage materials. [ABSTRACT FROM AUTHOR]

Abstract: High corrosion resistance Cu/Ni–P coatings were electrodeposited on AZ91D magnesium alloy via suitable pretreatments, such as one-step acid pickling-activation, once zinc immersion and environment-friendly electroplated copper as the protective under-layer, which made Ni–P deposit on AZ91D Mg alloy in acid plating baths successfully. The pH value and current density for Ni–P electrodeposition were optimized to obtain high corrosion resistance. With increasing the phosphorous content of the Ni–P coatings, the deposits were found to gradually transform to amorphous structure and the corrosion resistance increased synchronously. The anticorrosion ability of AZ91D Mg alloy was greatly improved by the amorphous Ni–P deposits, which was investigated by potentiodynamic polarization curve and electrochemical impedance spectroscopy (EIS). The corrosion current density (I corr ) of the coated Mg alloy substrate is about two orders of magnitude less than that of the uncoated. [Copyright &y& Elsevier]

Abstract: To investigate temperature-dependent ferroelectric and dielectric properties of ferroelectric films, Bi3.25La0.75Ti3O12 (BLT) thin films were prepared on Pt-coated silicon substrates by pulsed laser deposition. The ferroelectric and dielectric behaviors have been studied in a wide temperature range from 80K to room temperature. The saturated polarization (P sat) decreases with decreasing temperature and decreasing electric field, whereas remnant polarization (P r) shows a more complex temperature dependence. These results, which can be well explained based on a temperature-dependent charged defects–domain wall interaction model, might be helpful for further understanding the domain switching behavior. Based on these results, an alternative way to investigate temperature-dependent ferroelectric fatigue is proposed and experimentally carried out. The measured fatigue rate is found to be linearly dependent on temperature, consistent with the report on Pb(Zr,Ti)O3 films. Temperature-dependent dielectric measurements of the films further confirm the above explanation. [Copyright &y& Elsevier]

Abstract: Bi0.8La0.2FeO3/CoFe2O4 (BLFO/CFO) multilayer thin films (totally 20 layers BLFO and 19 layers CFO) were prepared on Pt/Ti/SiO2/Si substrates by pulsed laser deposition. X-ray diffraction and transmission electron microscope measurements show that the films are polycrystalline and consisted of multilayered structure. Ferroelectric hysteresis loops with remnant polarization and saturated polarization of 4.2 and 13.3μC/cm2, respectively, were observed. On the other hand, the films show well-shaped magnetization hysteresis loops with saturated and remnant magnetization of 34.7 and 11.4emu/cm3, respectively, which are significantly larger than pure BLFO thin films deposited under the same conditions. These results indicate that constructing epitaxial superlattice might be a promising way to fabricate multiferroics with improved properties. [Copyright &y& Elsevier]

Abstract: In this work, polyacrylonitrile (PAN)-based carbon fiber were chemically modified with H2SO4, KClO3 and silane coupling agent (γ-aminopropyltriethoxysilane, APS), and carbon fiber reinforced phenolic matrix composites were prepared. The structural and surface characteristics of the carbon fiber were investigated by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), laser Raman scattering (LRS) and Fourier transform infrared spectroscopy (FTIR). Single fiber mechanical properties, specific surface area, composite impact properties and interfacial shear strength (ILSS) were researched to indicate the effects of surface modification on fibers and the interaction between modified fiber surface and phenolic matrix. The results showed that carbon fiber surface modification by oxidation and APS can strengthen fiber surface chemical activity and enlarge the fiber surface area as well as its roughness. When carbon fiber (CF) is oxidized treatment, the oxygen content as well as the O/C ratio will be obviously increased. Oxygen functional groups increase with oxidation time increasing. Carbon fiber treated with APS will make Ch name="sbnd" />R content increase and Oh name="dbnd" />O content decrease due to surface reaction. Proper treatment of carbon fiber with acid and silane coupling agent prove an effective way to increase the interfacial adhesion and improve the mechanical and outdoor performance of the resulting fiber/resin composites. [Copyright &y& Elsevier]

• Ordered MnO x mesoporous materials were synthesized via the hard template method. • The ordering degree of mesoporous MnOx was regulated by preparation condition. • Ordered MnOx mesoporous materials exhibited strong selective adsorption for RhB. • Ordered MnOx mesoporous materials exhibited high catalytic H 2 O 2 oxidation for RhB. • Fe species loading could enhance the catalytic performance of the ordered MnO x. In this study, novel mesoporous MnO x -based catalysts were prepared via the hard template method by using the mesoporous silica as a template. The performances of these catalysts were evaluated in catalytic wet H 2 O 2 oxidation for Rhodamine B (RhB) in high-salinity wastewater (10% Na 2 SO 4 solution containing RhB). The microstructure characterization indicated that the order of pore structures and the MnO x crystallinity in mesoporous materials improved as the number of repetitions of the immersion and calcination–molding process increased. Given good selective adsorption performance for RhB and rich Mn3+/Mn4+ couples, MnO x mesoporous materials with ordered regular pores exhibited excellent Fenton-like catalytic performance and the highest removal rate of RhB in high-salinity wastewater reached approximately 90% after 150 min of degradation. Moreover, because of the accelerated generation of the free radicals catalyzed by the Fe3+/Fe2+ couples, the loading of Fe species increased the performance of the MnO x ordered catalysts for RhB degradation. Furthermore, the Fe-loading MnO x catalyst exhibited only slight activity loss within the five cycles of catalytic degradation (the removal rate for RhB within the five cycles all exceeded 95%), due to the morphological stability of the MnO x ordered catalyst and the presence of stable Fe3+/Fe2+ couples during the RhB degradation process. [ABSTRACT FROM AUTHOR]

Highlights: [•] Systematically and comparative microstructure analysis for the SrIrO3 thin films. [•] Meta-stable orthorhombic SrIrO3 phase was obtained under normal conditions. [•] The stabilization of meta-stable orthorhombic SrIrO3 was quantitatively understood by lattice mismatch strain. [ABSTRACT FROM AUTHOR]

Abstract: Orthorhombic YMnO3 thin films were epitaxially grown on bare and LaNiO3 buffered (001)–SrTiO3 substrates by pulsed laser deposition under various oxygen pressures from 5 to 30Pa. The crystal structure and microstructure of these films have been characterized by both X-ray diffractions and transmission electron microscopy. The leakage current, modeled as the space charge limited current (SCLC) mechanism, decreased significantly with the increase of oxygen content. It is further found that the magnetic property of films is greatly enhanced in YMnO3 films grown under high oxygen pressure, which can be explained decreased oxygen vacancies. In addition, bipolar switching behavior was obtained only in the films grown under 30Pa oxygen pressure, which is attributed to the decrease of voltage-driven oxygen vacancy migration. [Copyright &y& Elsevier]

Abstract: La-substituted BiFeO3, Bi0.8La0.2FeO3, thin films were fabricated on Pt/Ti/SiO2/Si substrates by pulsed laser deposition. X-ray diffraction and high-resolution transmission electron microscope were used to analyze the structures of the films. The results show the films fabricated under optimized growth condition are (012) textured. X-ray photoemission spectroscopy results indicate that the oxidation state of Fe ion is Fe3+ in the films without detectable Fe2+. The films show low leakage current and excellent dielectric characters. Multiferroic properties with a remnant ferroelectric polarization of 5.2μC/cm2 and a remanent magnetization of 0.02μB/Fe were established. These results have some implications for further research. [Copyright &y& Elsevier]

Abstract: 1–3 and 2–2 types Pb(Zr0.53Ti0.47)O3–CoFe2O4 (PZT–CFO) composite films with controllable microstructures, consisted by CFO nanopillar embedded in PZT matrix and PZT–CFO gratings respectively, have been fabricated on Pt/Ti/SiO2/Si substrates by combining lithography technology and pulsed laser deposition. X-ray diffraction confirms that the films are well crystallized under optimized postannealing conditions. Scanning electron microscope reveals that the periodic microstructures can be well controlled. Especially, intrinsic room temperature ferroelectric and ferrimagnetic behaviors are observed simultaneously. The structure–properties relationship is discussed. Our results may provide an alternative method to design and prepare multiferroic composite films with controllable microstructures. [ABSTRACT FROM AUTHOR]