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With manganese substituted heteropoly tungstate β2-K6[SiW11Mn(H2O)O39]·xH2O as the active component, a composite photocatalyst β2-SiW11Mn/TiO2 was prepared by impregnation method. The composite catalyst was characterized by FT-IR, UV-Vis, XRD, SEM and X-ray photoelectron spectroscopy. The catalytic activity was evaluated by the degradation of malachite green solution. The results showed that the degradation of malachite green under ultraviolet light reached 92.7% and the degradation effect under sunlight is better than that under ultraviolet light, reaching 97.2%. This indicates that polyoxometalates and titanium dioxide produced a synergistic effect to make the light response range expanded and reduced the reaction requirements. The catalytic degradation performance of pure titanium dioxide, heteropoly acid salt β2-SiW11Mn and the prepared catalyst β2-SiW11Mn/TiO2 on malachite green were studied. The results showed that the composite photocatalyst exhibited the best photocatalytic activity, confirming the significance of the material being compounded. Finally, the kinetics of the reaction were studied, and the reaction is a first-order reaction. [ABSTRACT FROM AUTHOR]

Micro/nano-structural polyaniline materials were prepared by using thin glass tubes as template in the presence of β2-SiW11Mn and ammonium persulfate, which were used as dopant and oxidant, respectively, in this system. The materials were characterized by IR, UV-Vis, XRD, TG-DTA and SEM techniques. The photocatalytic performance of polyaniline, β2-SiW11Mn and β2-SiW11Mn/PANI composite obtained was investigated using photodegradation of crystal violet as model reaction. The results showed that the photocatalytic activity of β2-SiW11Mn/PANI composite was much higher than polyaniline and β2-SiW11Mn due to a synergy between the two. The degradation rate of crystal violet was 91.19%. [ABSTRACT FROM AUTHOR]

Wastewater from the printing and dyeing industry is an area of growing concern. Photocatalysts synthesized using polyaniline (PANI) and certain metal oxides have been increasingly used for the purpose owing to their high photocatalytic potential, ease of synthesis, and ease of recycle and reuse. Herein, a ternary composite α-SiW11Cr/PANI/ZnO was prepared by electrostatic self-assembly, and characterized by infrared (IR) spectroscopy, diffraction of X-rays, scanning electron microscopy, etc. N2 adsorption-desorption showed that the composite had a bimodal pore system for mesoporous materials. Catalytic activity of α-SiW11Cr/PANI/ZnO for photodegradation of organic dye malachite green under UV irradiation was studied. Compared with single materials, ternary composites have better photocatalytic performance. [ABSTRACT FROM AUTHOR]

Graphene oxide was prepared by modified Hummers method, MnV13/GO composite was prepared by solution blending method, and MnV13/GO/PANI composite catalyst was prepared by interfacial method. The catalyst was characterized by ultraviolet-visible absorption spectroscopy (UV-Vis), infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and N2 adsorption-desorption. The results show that the V-O-V bonds of the polymerized heteropoly complex are blue-shifted and the V-Od bonds are red-shifted slightly from conjugation between V-Od and GO lamellae. The photocatalytic properties of the catalyst for malachite green showed that degradation of malachite green was 92.7% after 200 min of UV irradiation. The degradation under sunlight was better than that under ultraviolet light, reaching 97.2%. The degradation of malachite green by the catalyst is a first-order kinetic reaction. We find that such a MnV13/GO/PANI composite exhibits higher photocatalytic activity than MnV13/GO, MnV13 and GO toward the liquid-phase degradation of malachite green under both UV and sunlight irradiation. The presence of synergic effect between PANI and MnV13 is believed to play an essential role in affecting the photoreactivity. At last, the roles of active species in the photocatalytic process are compared by using different types of active species scavengers. The degradation mechanism of the photocatalysts is proposed. [ABSTRACT FROM AUTHOR]

In this article, the method of stepwise acidification, gradually charging and ion exchange was employed for synthesizing tungsten vanadium aluminum heteropoly acid catalysts and heteropoly acids-glycinesupramolecules. These novel products were further characterized through chemical analysis, IR, UV-Vis absorbance spectra, and X-ray diffraction analysis.The catalytic properties of these supramolecules were tested and prove the superior catalytic activity than most existing heteropoly acids. [ABSTRACT FROM PUBLISHER]

The purpose of this study is to develop a micro-actuator manufactured by microelectromechanical system-based fabrication and electroplating techniques. This actuator presents a novel technique in electromagnetic fabrication with a smaller physical size than its traditional counterparts and provides a faster response time at a lower cost. A micro-coil structure is released from FeCl3 etchant and bonded on a thin film (Parafilm ‘M’ Pechiney Plastic Packaging Inc.) to achieve an actuator-membrane structure. When an external AC power is applied to a micro-coil, a magnetic field is created to attract and repel through an NdFeB permanent magnet, and the displacement of the membrane is increased by AC. The results show that the measured magnetic field intensity weakens as the distance between the coil and the Gauss meter probe increases. However, it is observed that the magnetic field intensity does not increase linearly with the number of series coils, because of the distance between them. [ABSTRACT FROM AUTHOR]