Microwave-Assisted Synthesis of CdS-MOF MIL-101 (Fe) Composite: Characterization and Photocatalytic Performance.

The present study outlines the synthesis of cadmium sulfide-metal-organic framework (CdS-MOF) MIL-101 (Fe) heterojunctions achieved via fast microwave-assisted reactions. Thus, different CdS-MOF MIL-101 (Fe) ratios were prepared to study their effectiveness as photocatalysts. These compounds were employed in the photocatalytic degradation of methylene blue (MB) under UV and visible irradiation.

Evidence of a Thermal Diffusivity Gap in Sintered Li-Co-Sb-O Solid Solutions.

In this work, the thermal properties of ternary Li Co Sb O solid solutions are studied for different concentrations in the range 0 ≤ ≤ 0.7. Samples are elaborated at four different sintering temperatures: 1100, 1150, 1200 and 1250 °C.

Tailoring Heat Transfer and Bactericidal Response in Multifunctional Cotton Composites.

Through the execution of scientific innovations, "smart materials" are shaping the future of technology by interacting and responding to changes in our environment. To make this a successful reality, proper component selection, synthesis procedures, and functional active agents must converge in practical and resource-efficient procedures to lay the foundations for a profitable and sustainable industry. Here we show how the reaction time, temperature, and surface stabilizer concentration impact the most promising functional properties in a cotton-based fabric coated with silver nanoparticles (AgNPs@cotton), i.

Heat Transfer in Cassava Starch Biopolymers: Effect of the Addition of Borax.

In recent years, polymer engineering, at the molecular level, has proven to be an effective strategy to modulate thermal conductivity. Polymers have great applicability in the food packaging industry, in which transparency, lightness, flexibility, and biodegradability are highly desirable characteristics. In this work, a possible manner to adjust the thermal conductivity in cassava starch biopolymer films is presented.

Ce, Eu incorporation through doping of ALD-ZnO thin films for enhancing their photoluminescent properties.

Nanostructured ZnO nanoarrays deposited on silicon oriented substrates is a very promising area in the study of the control of physicochemical properties, in which photoluminescence plays a crucial role. This optical property inherent to ZnO, can be favorably modified through the inclusion of doping elements, with the purpose of appropriately modifying their optical absorption and luminescence. Following this objective, in the present work we present the development of ZnCeEuO nanostructured thin films.

"Tailoring the TiO phases through microwave-assisted hydrothermal synthesis: Comparative assessment of bactericidal activity".

Nanocrystalline titania (TiO) is one of the most investigated crystalline nanostructured systems in the field of materials science. The technological applications of this material are related to its optoelectronic and photocatalytic properties, which in turn are strongly dependent on the crystal phase (i.e.

Photocatalytic performance of nitrogen doped ZnO structures supported on graphene oxide for MB degradation.

In the present work, the photocatalytic efficiency of a novel system based on ZnO doped with nitrogen (ZT) and supported on graphene oxide (GO) is investigated. ZnO synthesis and their N doping were carried out in a microwave reactor using thiourea as nitrogen source, while the GO was prepared through a variation of the Hummers' method. Structural, morphological and photochemical characterization of the developed material was performed by X-ray diffraction (XRD), UV-Vis spectroscopy, energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), analysis by X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy.

Reversible Self-Assembly (fcc-bct) Crystallization of Confined Granular Spheres via a Shear Dimensionality Mechanism.

By combining vibrational annealing and shear dimensionality, we experimentally show (1) a fast reversible crystallization fcc-bct (face-centered cubic-body-centered tetragonal) in a granular system that is composed of dissipative millimeter-sized dry spheres, (2) a two-dimensional (planar) shear promotes self-assembly into an fcc crystal, while one-dimensional shear produces a bct crystal, and (3) in analogy with heterogeneous nucleation, a granular temperature gradient leads to the formation of crystal domains showing competition of polymorphic phases in the cold regions. Our findings suggest that controlling the directionality of the interactions steers to reversible crystallization of hard spheres, adds clues for theoretical studies, and provides a novel mechanism for the technological development of the applications of self-assembling phononic crystals.

Dehydration Process of Hofmann-Type Layered Solids.

In the present work the dehydration process of layered solids with formula unit M(H₂O)₂[Ni(CN)₄]·H₂O, M = Ni, Co, Mn; = 1, 2, 4 is studied using modulated thermogravimetry. The results show that water molecules need to overcome an energetic barrier (activation energy between 63 and 500 kJ/mol) in order to diffuse through the interlayer region. The related kinetic parameters show a dependence on the water partial pressure.

The nucleation kinetics of ZnO nanoparticles from ZnCl2 in ethanol solutions.

The first stages of the synthesis of ZnO nanoparticles by forced hydrolysis of ZnCl2 with NaOH and water in ethanol have been investigated using UV-Vis spectrophotometry. At sufficiently low water concentrations, focusing of the nanoparticle size distribution was observed during the nucleation and growth phase, followed by a defocusing phase when coarsening becomes significant. During nucleation and growth, only the smaller particles grow while the larger particles have an essentially zero growth rate, indicating that the growth rate decreases rapidly with particle size.

Hierarchically nanostructured barium sulfate fibers.

BaSO(4) nanostructures with controlled morphologies were successfully produced via one-step process through precipitation of BaSO(4) in aqueous and organic media. The synthesis is carried out by mixing solutions of BaCl(2) and Na(2)SO(4) in presence of EDTA (disodium ethylenediaminetetraacetic acid) at room temperature. The influence of the reaction conditions such as initial reactants concentration, pH, EDTA/[Ba(2+)] ratio and aging on the BaSO(4) nanoparticles organization is studied.

Direct interaction of colloidal nanostructured ZnO and SnO2 with NO and SO2.

A novel and easy synthesis pathway of small SnO2 nanoparticles is reported. The method consists of the spontaneous hydrolysis of SnCl4 x 5H2O in dimethyl sulfoxide (DMSO), containing 3% water, at room temperature. The structure of the SnO2 nanocrystals corresponds to that of the cassiterite phase, as shown by powder X-ray diffraction and HR-TEM.

A combined theoretical-experimental study on the acidity of WO(x)-ZrO(2) systems.

This work provides a chemical approach to the relationship between structure and electronic behavior of the active surface of the WO(x)-ZrO(2) system as a function of W loads. This study shows that the electronic hardness (eta), the Lewis and Brønsted acidity are functions of the local coordination and of the polymerization degree of the WO(x) domain. From theoretical calculations the observed behavior in the WO(x)-ZrO(2) system is explained: the Brønsted acidity increases while the Lewis acidity decreases as the W centers go from tetrahedral to octahedral coordination and as the condensation degree of the WO(x) domain increases.

Phase-pure TiO(2) nanoparticles: anatase, brookite and rutile.

We report on the synthesis of phase-pure TiO(2) nanoparticles in anatase, rutile and brookite structures, using amorphous titania as a common starting material. Phase formation was achieved by hydrothermal treatment at elevated temperatures with the appropriate reactants. Anatase nanoparticles were obtained using acetic acid, while phase-pure rutile and brookite nanoparticles were obtained with hydrochloric acid at a different concentration.

Synthesis and characterization of RuS2 nanostructures.

Small naked ruthenium sulfide nanoparticles (NPs) with narrow size distribution (2.5 +/- 0.4 nm of diameter) were synthesized in DMSO colloidal dispersions, under mild reaction conditions and using commercial RuCl3 as precursor.

New insights on molybdenum suboxide: nature of carbons in isomerization reactions.

MoO3 transformations under isomerization process conditions were studied. The products obtained after different times under stream (H2/n-heptane mixture, 18.5 bar, at 370 degrees C) were characterized by X-ray diffraction, Raman spectroscopy, thermal analysis, and high-resolution transmission electron microscopy (HRTEM).

Optical absorbance of colloidal suspensions of silver polyhedral nanoparticles.

The optical absorption of colloidal suspensions made of silver nanoparticles with polyhedral shapes is studied experimentally and theoretically. The influence of the shape on the optical response is investigated by comparing the measured absorbance with theoretical results for icosahedral, decahedral, and cuboctahedral silver nanoparticles. The theoretical spectra are obtained within the discrete dipole approximation.

One-step synthesis of Mn3O4 nanoparticles: structural and magnetic study.

One-step room-temperature synthesis of nanocrystalline Mn3O4 hausmannite, without heating posttreatment, was carried out from a simple dissolution of manganese(II) acetate in a mixture of N,N'-dimethylformamide (DMF) and water. Homogeneous nanocrystals like rods were obtained, with an average width and length of 6.6+/-1.

Synthesis of ZnO nanoparticles on a clay mineral surface in dimethyl sulfoxide medium.

Nanocrystalline ZnO particles have been prepared with different methods using zinc cyclohexanebutyrate as precursor in dimethyl sulfoxide (DMSO) medium via alkaline hydrolysis. A series of preparations were carried out in the presence of layered silicates (kaolinite and montmorillonite). It was revealed by different measurement techniques that the presence of the clay minerals has a stabilization influence on the size of the ZnO nanocrystals.