Shengsong Ge

The facile preparation of novel magnetic zirconia composites with the aid of carboxymethyl chitosan and their efficient removal of dye

Novel composites based on magnetic zirconia was synthesized with the aid of carboxymethyl chitosan (Fe3O4/ZrO2–CMCS) by a facile method. The as-synthesized products were characterized by wide-angle powder X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR). The magnetic zirconia carboxymethyl chitosan (Fe3O4/ZrO2–CMCS) composites consisted of particles which show a better regularity and uniform with 200–300 nm in diameter. The as-obtained Fe3O4/ZrO2–CMCS nanocomposites exhibited high adsorption activity and the adsorption capacity for sunset yellow was up to 143.2 mg g−1 without adjusting pH of the solution. Interestingly, after the carboxymethyl chitosan being eliminated by calcining in air, the as-obtained Fe3O4/ZrO2 showed enhanced photocatalytic activity under sunlight irradiation. The degradation rate of rhodamine B as well as sunset yellow was 89% and 84% in 240 min, respectively, due to the addition of the Fe3O4/ZrO2 photocatalyst under sunlight irradiation. Both Fe3O4/ZrO2–CMCS and Fe3O4/ZrO2 can be recycled and reused easily, due to magnetism of iron oxide in the composites. Considering the high adsorption performance of Fe3O4/ZrO2–CMCS and the enhanced photocatalytic activity of Fe3O4/ZrO2 for dye stuff, these two nanocomposites can be applied in treating the waste water contaminated by organic dye stuff.

Yeast-template synthesized Fe-doped cerium oxide hollow microspheres for visible photodegradation of acid orange 7.

Fe-doped cerium oxide (CeO2) hollow microspheres were successfully synthesized by a simple co-precipitation route using yeast asa bio-template and nitrate as the oxide precursor. The products were characterized by scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, N2 adsorption-desorption isotherms and UV-Vis diffuse reflectance spectroscopy. It was found that the products had a well-defined ellipsoidal morphology and the size of the hollow microspheres was about 1.5-2.5μm. The formation mechanism of Fe-doped CeO2 hollow microspheres was proposed and discussed as well. The photocatalytic test results showed that the Fe-doped CeO2 hollow microspheres exhibited a higher photocatalytic activity in the degradation of acid orange 7 (AO7) aqueous solutions containing H2O2 under visible irradiation compared with CeO2 hollow microspheres and Fe-doped CeO2 nanoparticles, which was attributed to their more oxygen vacancies, higher specific surface area and lower band gap. The degradation rate of the Fe-doped CeO2 hollow microspheres was found to be 93% after 80min and the degradation reaction followed pseudo-first-order kinetics.

Synthesis of 3,4,5-trihydroxy-2-[(hydroxyimino) methyl] benzoic acid as a novel rust converter

ABSTRACT A new rust converter, 3,4,5-trihydroxy-2-[(hydroxyimino) methyl] benzoic acid (named as RC-GAO), has been synthesized based on gallic acid by formylation and oximation. The synthesis was confirmed by Fourier transform infrared spectroscopy studies. The nature and morphology of rust and conversion layer on the rusty samples were characterized by scanning electron microscopy and X-ray diffraction. The corrosion resistance of the residual rust coatings containing the rust converter on the rusty sample was measured by the salt spray test. The results showed that the synthesized rust converter possessed excellent chelating capability with rust and significant anticorrosive performance. The synthesized rust converter revealed excellent chelating capability with rust and significant anticorrosive performance GRAPHICAL ABSTRACT

Electrodeposition Synthesis of Polyaniline-Modified TiO2 Nanotube Arrays with Enhanced Photoelectrochemical Property

Polyaniline-modified TiO2 nanotube arrays (PANI/TNTs) were fabricated by a constant voltage electropolymerization method. The self-organized TiO2 nanotube arrays with an inner diameter of approximately 100 nm and a length of 4 μm were prepared by a two-step anodization at 20 V for 3 h, and then the polyaniline was deposited on the surface of the TiO2 nanotube arrays. The phase composition, morphology and property of PANI/TNTs were characterized by X-ray diffraction, scanning electron microscopy, fourier transform infrared spectroscopy and UV-vis diffuse reflectance spectroscopy. The prepared PANI/TNTs showed enhanced visible light absorption and corresponding visible light photocatalytic activity. Furthermore, the PANI/TNTs also exhibited higher electrochemical behaviour than that of TiO2 nanotube arrays.

Solvothermal synthesis, characterization and photocatalytic property of zirconium dioxide doped titanium dioxide spinous hollow microspheres with sunflower pollen as bio-templates

Zirconium dioxide (ZrO2) doped titanium dioxide (TiO2) spinous hollow microspheres were successfully prepared through a facile solvothermal method using sunflower pollen as bio-templates. The products were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), N2 adsorption-desorption isotherms and UV-Vis diffuse reflectance spectroscopy. It was found that the products have spinous microsphere morphology with an approximate diameter of 12 μm. The ZrO2 doped TiO2 hollow microspheres exhibited a higher photocatalytic activity in the degradation of Rhodamine B (RhB) in aqueous solutions under UV-light irradiation compared with TiO2 hollow microspheres and ZrO2-doped TiO2 particles. In particular, the removal of RhB followed pseudo-first-order kinetics, and 96.3% of RhB was degraded in 60 min under UV-light irradiation when ZrO2 doped TiO2 spinous hollow microspheres were used as the photocatalysts. Neutral and alkaline conditions were found to favor over acidic conditions for the photocatalytic degradation of RhB. Furthermore, scavenging experiments indicated that photogenerated holes (h+) and radicals (OH and O-2) were the main reactive species in the photocatalytic process using ZrO2 doped TiO2 hollow microspheres as the catalysts under UV light irradiation.

Effect of metal ions on the anti-corrosion properties of γ-glycidoxypropyltrimethoxysilane coatings on cold-rolled iron

Purpose – This paper aims to clarify the effect of metal ions added in the γ-glycidoxypropyltrimethoxysilane (γ-GPS) solutions on the anti-corrosion properties of the γ-GPS coatings on cold-rolled iron (CRI). Design/methodology/approach – The transformations of functional groups involved in reactions during the coating process were characterized by Fourier transformed infrared spectroscopy (FTIR), and the thickness of the γ-GPS coatings on the CRI substrates was measured using high-powered microscopy. The anti-corrosion properties of γ-GPS-treated samples were evaluated by neutral salt spray tests, polarization curves and electrochemical impedance spectroscopy measurements. Findings – The results show that Zn2+ and Mg2+ in the γ-GPS solutions promote the formation of Si-O-Si and Si-O-Fe bonds and improve the anti-corrosion properties of the γ-GPS coatings on CRI. However, Al3+ and Na+ in the γ-GPS solutions do not play this role. Originality/value – Although there have been previous research studies on th...