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Abstract: Tungsten oxide (WO3) is one of the most promising materials for electrochromic devices and is currently investigated for applications in catalysis, ferroelectricity and in sensor technology. Here a molecular assembly approach to synthesize by sol–gel meso and macroporous thin films of tungsten oxide using polyethylene-glycol as a templating agent is reported. Micro-Raman spectroscopy has been employed to investigate the structure of WO3 thin films, deposited by dip-coating on glass, as a function of thermal annealing. This modified sol–gel route promotes the coexistence of a sub-stoichiometric monoclinic phase (most probably the WO2.72 phase) together with some hydrous phases (WO3·nH2O) even in samples heat treated up to 500 °C. [Copyright &y& Elsevier]

Abstract: Domoic acid (DA) is a water-soluble marine neurotoxin produced and released by Pseudo-nitzschia species. It is remarkably pervasive in North American coastal waters, where it is a threat to public health and some marine life, and has resulted in severe economic losses in the shellfish and crustacean harvesting industry. In this paper we report on the development of nanocrystalline titania thin films that were used as photocatalyst in the UV photodegradation of DA. TiO2 thin films produced by a sol–gel dip-coating method in the presence of polyethylene glycol (PEG) of different molecular weights (200, 400 and 600), were deposited on glass and fused quartz substrates, and crystallized at different temperatures (90, 500 and 900°C). The films were characterized using UV–vis, FTIR, SEM, XRD, and Raman spectroscopy. For the photocatalytic activity measurements, the TiO2 films were immersed in a DA solution (2500ng/mL) and exposed for various times at room temperature to UV irradiation (λ ∼350nm). DA analysis was carried out by HPLC, and the photocatalytic activity was quantified as the rate of disappearance of DA. The photocatalytic activity of the TiO2 thin films was studied as a function of their crystallization temperature, type of PEG content, and thickness. The films prepared at low temperature proved to be very efficient photocatalysts. They showed a higher photocatalytic activity than those produced at high temperature. Also, using PEG of higher molecular weight in the TiO2 coating solutions increased the effectiveness of the degradation. When using UV irradiation alone, without photocatalyst, the degradation of DA was not significant. The presence, transformation, and degradation of various DA isomers were observed during the photodegradation process, and a photodegradation mechanism is proposed. [Copyright &y& Elsevier]

Abstract: Tungsten oxide (WO3) is one of the most promising materials for electrochromic devices. In this paper, we report on a simple route for the low temperature synthesis of nanocrystalline WO3 films involving treatment of tungsten hexachloride and non-ionic tri-block copolymer surfactant at 100°C. The films were studied by Raman spectroscopy and transmission electron microscopy (TEM) for their structural properties and also by scanning electron microscopy (SEM) to understand it’s microstructure. Raman studies show the presence of different nanocrystalline phases (m-WO3, and WO3 ·1/3 H2O) embedded in an amorphous matrix. A TEM diffraction pattern shows the nanocrystalline nature and a preferred growth direction for the crystallites. An electrochromic system using the low temperature WO3 film as an active electrode was fabricated and tested. [Copyright &y& Elsevier]

TiO2 nanocrystalline thin films with varying degree of porosity have been prepared using a low temperature method. TiO2 films of the anatase form have been obtained by using a polyethylene glycol (PEG) modified sol-gel method. Densification and crystallization of the films was found to result from the thermal treatment of the dip coated films in boiling water. The films have been characterized by Raman, XRD, FTIR, AFM and optical methods. Highly transparent films with transmission in excess of 85% and porosity as high as 58% are formed predominantly of anatase crystallites of dimensions of the order of 5 nm. Initial results on lithium intercalation into these films resulting in an efficient optical modulation in the visible and near infrared regions demonstrate a good potential of these films for electrochromic applications. [ABSTRACT FROM AUTHOR]

Abstract: Mesoporous vanadium pentoxide (V2O5) films have been synthesized by hydrolysis of vanadium tri-isopropoxide (VO(OC3H7)3) in the presence of polyethylene glycol (PEG) as a structure-directing agent. The structure, the stoichiometry and the morphology of the films have been studied as a function of the thermal annealing by X-ray diffraction (XRD), micro-Raman spectroscopy, optical microscopy, scanning electron microscopy and atomic force microscopy. XRD patterns and Raman spectra show the presence of two previously unreported crystalline phases. The PEG:V2O5 molar ratio affects the temperature of phase formation, the amount and even the order in which the phases appear. The morphological characterization underlines the role of the surfactant to promote porous networks, formed by micrometric clusters of controlled shapes and patterns embedded in a homogeneous host matrix. [Copyright &y& Elsevier]

Abstract: Tungsten oxide (WO3) is one of the most promising materials for electrochromic devices. WO3 thin films have been prepared at low temperature by using a polyethylene glycol (PEG) assisted sol–gel method. The structure and the stoichiometry of films deposited by dip coating on glass substrates have been studied as a function of thermal annealing by XRD, FTIR and μ-Raman. PEG-containing samples show improved electrochromic efficiency due to the formation of sub-stoichiometric, nanocrystalline phases. The electrochromic performance of WO3 films gets worse for annealing temperatures higher than 300°C due to massive Na absorption from the substrate. [Copyright &y& Elsevier]

The open-layered structure of Vanadium pentoxide (V 2 O 5 ) has triggered significant interest in exploring its energy-related application as lithium (Li) intercalation cathode material. Various methods are extensively studied to improve the Li diffusion using thin films or nanoarchitecture. In this work, high-quality two-dimensional (2D) inverse opal α-V 2 O 5 films were synthesized via a modified 'dynamic hard template' infiltration strategy using sacrificial polystyrene spheres (PS, a diameter of 530 nm) photonic crystal as a template. The new material exhibited an excellent porous array with featured structural colors in a large area. The electrochromic behavior was explored by combining bandgap and electrochemical characterization. On the one hand, the intercalation/deintercalation of Li + played an important role in the bandgap (Eg), and thereafter on the visible range transmittance through changing the film's stoichiometry and the valence of vanadium ions. On the other hand, the asymmetry of the lattice due to the disordered distribution of Li + within the V 2 O 5 interlayer and/or the formation of an irreversible phase explained the change in transmittance with voltage.

Pure anatase two dimensional (2D) TiO 2 inverse opal (IO) films, consisting of a highly ordered hexagonal-patterned structure, are synthesized from various sized polystyrene spheres (PS) as colloidal template simply coupled with TiOSO 4 aqueous solution as TiO 2 precursor using a "dynamic-hard-template infiltration" strategy. Herein, the TiOSO 4 solution is directly infiltrated into the interstices of the 2D self-assembled PS opal template at an air/water interface resulting in a TiOSO 4 /PS opal composite film floating on the surface of water which was further deposited onto ITO or silicon substrates. Calcination of the obtained opal composite films at temperatures ranging from 300 to 550 °C resulted in 2D TiO 2 IO films with various pore sizes having an inverse moth's eye structure. Based on EDS measurements, sulfur ions S 6+ were detected in the IO films calcined up to 550 °C. In order to eliminate these S 6+ ions and obtain pure anatase 2D TiO 2 IO, aqueous immersion was performed after calcination without disturbance of the IO ordered structure. Surface morphology, crystal phase and optical transmittance of the TiO 2 IO films, were concurrently investigated by SEM, Raman and UV-vis-NIR. Owing to their precisely adjustable structure, the obtained TiO 2 2D IO films exhibited structural colors varying from pale purple, to blue, to polychrome as the array period increases. The films obtained on ITO substrates were successfully used as active electrodes in the fabrication of electrochromic (EC) devices., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Composite materials aimed at bone tissue engineering need to have suitable bioactivity in order to promote cell proliferation and adhesion. In this article, we study the potential of boronic acids to improve the bioactivity of chitosan-based composite materials. Samples were prepared using boronic acid functionalised chitosan and Bioglass 45S5. These composite materials, prepared by freeze-drying, exhibit 3D interconnected porosity. The materials were fully characterized using scanning electron microscopy (SEM), FT-IR and x-ray diffraction. Their bioactivity was assessed by immersion in simulated body fluid and cell cytotoxicity assays. Composite materials containing boronic acid show no toxicity for Mouse Sertoli (TM4), Human embryonic kidney 293 (Hek293) and Human bone marrow/stroma (HS-5) cells, as opposed to composites containing non-functionalised chitosan., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

A hierarchically porous anatase TiO2 coated-WO3 2D inverse opal (IO) bilayer film was fabricated on ITO glass using a layer by layer route with a hierarchically porous TiO2 top layer and an ordered super-macroporous WO3 2D IO bottom layer. This novel TiO2 coated-WO3 2D IO bilayer film was evaluated for photochromic applications.

Northern shrimp (Pandalus borealis) oil, which is rich in omega-3 fatty acids, was recovered from the cooking water of shrimp processing facilities. The oil contains significant amounts of omega-3 fatty acids in triglyceride form, along with substantial long-chain monounsaturated fatty acids (MUFAs). It also features natural isomeric forms of astaxanthin, a nutritional carotenoid, which gives the oil a brilliant red color. As part of our efforts in developing value added products from waste streams of the seafood processing industry, we present in this paper a comprehensive characterization of the triacylglycerols (TAGs) and astaxanthin esters that predominate in the shrimp oil by using HPLC-HRMS and MS/MS, as well as 13C-NMR. This approach, in combination with FAME analysis, offers direct characterization of fatty acid molecules in their intact forms, including the distribution of regioisomers in TAGs. The information is important for the standardization and quality control, as well as for differentiation of composition features of shrimp oil, which could be sold as an ingredient in health supplements and functional foods.

A 'dynamic hard-template' infiltration strategy for crack-free large-area synthesis of 2D WO3 inverse opal (IO) films on ITO substrates using a wide range of sizes of sacrificial PS spheres is reported. Thus prepared WO3 IO films were successfully used as an active electrode in the fabrication of an electrochromic device.

Porous silica materials S8, S12, S16, and SBA with controllable pore structures and morphology were synthesized by varying the type or alkyl chain length of the surfactant. Diverse amino-functionalized organic-inorganic hybrid porous materials were then prepared by post-grafting. Depending on the relation between the pore diameter of the porous silica materials and the size and content of the moiety to be grafted, the functionalized materials exhibited varying degrees of decline of structure properties, i.e. regular arrangement of pores, specific surface area, pore size, and pore volume. The hybrid silica materials have been employed as heavy metal ions adsorbents from simulated drinking water at room temperature. The results indicated that the diverse pore structures and different amino group densities influence the heavy metal ions adsorption of functionalized silicas significantly. The best adsorbent was found to be monoamino-functionalized silica S16-1N, which could effectively remove heavy metal Cd(II), Pb(II), Fe(III), as well as Mn(II). The good performance can be attributed to the accessibility of effective amino groups in the pores, as well as the suitable pore structure with high specific surface area of 728 m(2)/g and total pore volume of 0.34 cm(3)/g., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Tungsten trioxide (WO(3)) nanostructures were synthesized by hydrothermal method using sodium tungstate (Na(2)WO(4).2H(2)O) alone as starting material, and sodium tungstate in presence of ferrous ammonium sulfate [(NH(4))(2)Fe(SO(4))(2).6H(2)O] or cobalt chloride (CoCl(2).6H(2)O) as structure-directing agents. Orthorhombic WO(3) having a rectangular slab-like morphology was obtained when Na(2)WO(4).2H(2)O was used alone. When ferrous ammonium sulfate and cobalt chloride were added to sodium tungstate, hexagonal WO(3) nanowire clusters and hexagonal WO(3) nanorods were obtained, respectively. The crystal structure and orientation of the synthesized products were studied by X-ray diffraction (XRD), micro-Raman spectroscopy, and high-resolution transmission electron microscopy (HRTEM), and their chemical composition was analyzed by X-ray photoelectron spectroscopy (XPS). The optical properties of the synthesized products were verified by UV-Vis and photoluminescence studies. A photodegradation study on Procion Red MX 5B was also carried out, showing that the hexagonal WO(3) nanowire clusters had the highest photodegradation efficiency.