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A novel nanocomposite (WO3/UiO-66) was successfully synthesized by the microwave hydrothermal method. The influence of the W:Zr molar ratio on the WO3/UiO-66 structure was explored in detail, and the photocatalytic activity of the nanocomposite for photodegradation of rhodamine B (RhB) was evaluated. The WO3/UiO-66 with a W:Zr molar ratio of 1:5 (WO3/UiO-66–5) exerted the most excellent photocatalytic performance, and the photocatalytic efficiency reached 96.6% after 100 min of simulated sunlight irradiation, thereby showing a higher photocatalytic performance than pure UiO-66 or pure WO3. In addition, the stability and reusability of the nanocomposite were studied by cyclic experiments, and the degradation rate of WO3/UiO-66–5 still reached 86.6% after 5 cycles. The mechanism underlying the photocatalytic degradation of WO3/UiO-66 was finally studied by quenching tests, and the crucial factor in the RhB degradation was hole (h+), and the existence of the n–n heterojunction also promotes the degradation of RhB by nanocomposites. In this work, an effective method is provided for the preparation of photocatalysts that degrade organic dyes.

A series of C-doped ZnO/TiO2 composites with various molar ratios of ZnO to TiO2 were synthesized by one-step controllable pyrolysis of Zn/Ti bimetallic metal-organic frameworks (Zn/Ti-MOF). The Zn/Ti-MOF was prepared using a facile microwave hydrothermal method. Electron microscopic analysis proved that the composites presented regularity cubic morphology with an edge length of about 1 μm and the C atoms were successfully doped into ZnO/TiO2 composites. X-ray photoelectron spectroscopy (XPS) measurement results confirmed the C-doping in the ZnO/TiO2. Comparative experimental studies showed that 2% ZnO/TiO2 composites prepared with the calcination temperature of 600℃ displayed the best photocatalytic degradation efficiency (94%) of RhB under the simulated sunlight irradiation. Cyclical experiment indicated the high stability and reusability of 2% ZnO/TiO2 composites. Electron spin resonance (ESR) and trapping experiments illustrated that the produced O2− served as the main active species for the efficient RhB removal. This work provides an efficient way for preparing C-doped bimetal oxides composites, which would have an important application prospect in the photocatalytic degradation of organic pollutants in environmental water.

A new bimetallic metal–organic framework (Cd/Zr-MOF) was successfully synthesized via microwave hydrothermal method using Zr4+ and Cd2+ as two metal ions and terephthalic acid (H2BDC) as organic ligand. The effects of Cd/Zr molar ratio and the reaction temperature on the Cd/Zr-MOF structure and its photocatalytic performance to degrade Rhodamine B (RhB) under simulated sunlight were explored in detail. The results show that the Cd/Zr-MOF with Cd/Zr molar ratio of 5:1 obtained at the reaction temperature of 160 °C exhibits the best photocatalytic performance, and the photocatalytic efficiency can reach 95.82% after 105 min irradiation, which is much higher than that of pure UiO-66 or pure Cd-MOF. The result of Mott–Schottky tests certified the formation of n–n heterojunction between Cd-MOF and UiO-66, which is conducive to the transfer and separation of photogenerated electrons and holes and is the main reason of the enhanced photocatalytic performance. In addition, the mechanism of photocatalytic degradation of Cd/Zr-MOF was studied by adding different eliminating agents. The photodegradation of RhB was mainly caused by superoxide ion (·O2−) and electron hole (h+). The Cd/Zr-MOF composites with excellent photocatalytic activity to Rhodamine B were synthesized via one-step microwave hydrothermal method.

The precursor particles were successfully prepared by a facile microwave hydrothermal method. Compared with solvothermal and precipitation method, microwave hydrothermal method can greatly shorten the reaction time and increase the product yields. Nitrogen (N) doped zinc oxide (ZnO) nanoparticles were derived via one-step controllable pyrolysis of zeolitic imidazolate framework-8 (Zif-8) precursors under 550 °C. The powder X-ray diffraction (XRD) analysis, elemental mapping image, energy dispersive spectrometry (EDS) spectra and X-ray photoelectron spectroscopy (XPS) analysis proved that Zif-8 particles were converted to ZnO and the N atoms were successfully doped into ZnO lattice. The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) results demonstrated that N doped ZnO retained the morphology of Zif-8 with a particle size of approximately ~70 nm and the UV–visible diffuse reflectance spectra (UV–vis DRS) showed that the as-prepared N doped ZnO possessed a lower band gap (3.16 eV) than commercial ZnO (3.26 eV). The photocatalytic activities of the as-prepared samples were evaluated by the degradation rate of methylene blue (MB) upon irradiation with solar-simulated light. The photocatalytic degradation efficiency of N doped ZnO was 95.3% after 80 min illumination, which was much higher than that of other samples prepared by other methods. Quenching tests proved that the photo-generated holes (h+) played a main role in the photodegradation of MB under solar-simulated light irradiation.

The core-shell acrylic emulsion was prepared by semicontinuous seeded emulsion polymerization with acrylic monomers as the main raw materials and the octafluoropentyl methacrylate (OFPMA) as modified monomers. And the influence of OFPMA on the hydrophobicity, thermal stability and mechanical properties of acrylic emulsion film was investigated. Fourier transform infrared spectroscopy (FTIR) analysis and X-ray photoelectron spectroscopy (XPS) all indicated that the OFPMA was successfully introduced to the acrylic emulsion. TEM image shows that the emulsion particles have a core-shell structure. The addition of OFPMA reduces the water absorption rate (3.2 %) of the coating film and improves its water resistance. Contact angle of coating surface increased from 80.7° to 90.7°. Moreover, TGA curves showed that the addition of OFPMA increased the initial decomposition temperature of the polymer from 355 ℃ to 370 ℃. Additionally, with the addition of OFPMA, the mechanical properties of modified polymers were also improved compared to pure acrylic resin. The application of the core-shell structure reduces the amount of fluorine-containing acrylic monomers, reduces environmental pollution, and improves economic benefits. This study provides a kind of environmentally friendly waterborne acrylic resin and a simple method for optimizing the performance of waterborne resins.

The nano-oxide materials with special structures prepared by template methods have a good dispersion, regular structures and high specific surface areas. Therefore, in some areas, improved properties are observed than conventional bulk oxide materials. For example, in the treatment of dye wastewater, the treatment efficiency of adsorbents and catalytic materials prepared by template method was about 30 % or even higher than that of conventional samples. This review mainly focuses on the progress of inorganic, organic and biological templates in the preparation of micro- and nano- oxide materials with special morphologies, and the roles of the prepared materials as adsorbents and photocatalysts in dye wastewater treatment. The characteristics and advantages of inorganic, organic and biological template are also summarized. In addition, the applications of template method prepared oxides in the field of sensors, drug carrier, energy materials and other fields are briefly discussed with detailed examples.

Carbon nanotubes (CNT)-cerium oxide (CeO2) nanocomposites were fabricated successfully by one-pot microwave hydrothermal growth of regular CeO2 nanoparticles with a size of 8 nm on hydroxyl-functionalized multi-walled CNTs. These nanocomposite photocatalysts demonstrated an acid orange (AO7) photocatalytic degradation efficiency of above 90% under solar-simulated light irradiation for 3 h, which was much higher than that of the pure CeO2 nanoparticles. The enhanced photocatalytic activity was observed to mainly originate from the ˙O2- and hole traps, while the hydroxyl radical ˙OH played a secondary role.

One major obstacle in the advancement of proton exchange membrane (PEM) technology is the development of highly active and durable electrocatalysts for the oxygen evolution reaction (OER) in an aci...

The development of highly effective, universal, and economical electrocatalysts for hydrogen evolution reaction (HER) via structure modulations remains a great challenge. Herein, we propose a novel solidoid nitridation reduction method to synthesize α-MoC1–x quantum dots encapsulated in nitrogen-doped carbon (α-MoC1–x/NC) with a shape like “frog eggs”. Carbon nitride was first prepared by pyrolysis of urea and then mixed with ammonium molybdate tetrahydrate under a temperature-programmed reduction. With the assistance of nitrogen release during thermal treatment, N doping and an ultrathin porous structure were obtained. Benefiting from the strong interaction of α-MoC1–x quantum dots and nitrogen-doped carbon, the α-MoC1–x/NC delivered an outstanding performance toward HER at all pH values. Here, 118 mV, a lower overpotential, is needed to reach 10 mA cm–2 in alkaline solution, and the current density of α-MoC1–x grew much faster than the commercial Pt/C with increased potential. And, this can keep steadil...

The development of novel and highly efficient bifunctional electrocatalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is an ongoing challenge. The Cr3+ cati...

A series of C-doped ZnO/TiO

C-doped ZnO particles have been successfully prepared by the calcination using microwave hydrothermally prepared metal-organic framework-5 (MOF-5) as the precursor. MOF-5 was turned into C-doped ZnO through calcination at 500 °C, and its cubic shape was well-maintained. X-ray photoelectron spectroscopic studies confirmed the C-doping in the ZnO. The as-prepared C-doped ZnO demonstrated a Rhodamine B (RhB) degradation efficiency of 98% in 2 h under an solar-simulated light irradiation, much higher than that of C-doped ZnO derived from MOF-5 synthesized by the ordinary hydrothermal method. The trapping experiment revealed that the crucial factors in the RhB removal were photogenerated h

Indium oxide (In2O3) doped zinc oxide (ZnO) nanocomposites were successfully synthesized through a facile microwave hydrothermal method. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), N2 adsorption–desorption isotherms (BET) and UV-Vis diffuse reflectance spectroscopy. The morphology of In2O3-ZnO composites was observed to be like flowers, and the diameter of particles constituting the porous petal was about 30 nm. The photoelectrocatalytic test results showed that the photoelectrocatalytic methylene blue (MB) degradation efficiency using In2O3-ZnO nanocomposites as photocatalysts under visible light irradiation and a certain voltage could reached above 95.3% after 60 min, much higher than that of In2O3 particles and ZnO particles. The enhanced photoelectrocatalytic activity was attributed to the doping of In2O3 and applied voltage, which beneficially reduced the recombination of electrons and holes in the photoelectrocatalytic process, therefore, it promoted the production of active species (•OH and •O−2).

NiFe layered double hydroxides (NiFe-LDHs) have been regarded as significant electrocatalysts for the oxygen evolution reaction (OER). However, their overpotential must still be further reduced to enable commercial applications. Herein, a promising and highly effective "hydroxyl ions hungry" electrode structure was prepared for the first time via a two-step hydrothermal reaction procedure to enhance the surface adsorption kinetics to obtain an ultralow overpotential. The electrode exhibits OER activity with ultralow overpotentials of 203 mV and 293 mV at the current densities of 10 mA cm-2 and 100 mA cm-2, respectively, in 1.0 M KOH. These results reveal an important way to improve the catalytic performance in an alkaline medium.

Visible-light-responsive ZnO/NiO/In2O3 mixed metal oxide (ZNI-MMO) photoelectrocatalysts with different Ni/In molar ratios were derived from corresponding ternary hydrotalcite-like precursors follo...

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.

Novel waterborne acrylic resin modified with glycidyl methacrylate (GMA) was successfully synthesized via homogeneous solution polymerization in isopropyl alcohol followed by solvent exchange with water. Aminopropyltriethoxysilane (KH-550), a silane coupling agent that can crosslink with resin and iron base material, was used as curing agent for solidifying this GMA modified resin. The cured mechanism of the coating was also investigated by 29Si nuclear magnetic resonance (29Si NMR) spectra and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR). The waterborne acrylic resin was sprayed on the iron base material and cured by KH-550 for 30 min at 100 °C to form the desired coating. The GMA and KH-550 were found to significantly decrease the curing temperature of this two-component waterborne resin. The thermal property of the coatings with different GMA loadings was investigated using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The GMA enhanced the thermal stability of the coatings from 100 to 400 °C. The modification of GMA was found to reinforce significantly the mechanical properties of the coatings. The tensile strength of coating modified with 15 wt% GMA got a 78.65% improvement compared to that of unmodified resin. The surface hydrophobicity of the coatings does get affected by this modification. The contact angle got increased from 87.72°of the unmodified resin coating to 99.51°of coating modified with 15 wt% GMA. This work opens a new way to synthesize high performance waterborne acrylic resin and reports on the anti-flash corrosion of waterborne coatings on the iron base material surface.

A novel water-based rust converter 2-hydroxypropyl 3, 4, 5-trihydroxybenzoate (named as RC-GAE) was prepared by using an esterification reaction between 1, 2-propylene glycol (PG) and gallic acid (GA). The effects of PG and GA mass ratio in the RC-GAEs on the anticorrosion were investigated by the Tafel polarization with the rusty plate samples coated with RC-GAEs in a 3.5 wt% NaCl solution. The rust was converted to a compact black protective rust-conversion film with this rust converter. The metallographic microstructure, morphology, and crystalline phase of the rust-conversion films were conducted systematically by optical microscopy, X-ray diffraction, and scanning electron microscopy with energy-dispersive spectrometry. The corroded plate with uneven and rough brown surface became smoother and darker after treated with converter. X-ray photoelectron spectroscopy indicated that the RC-GAE reacted with Fe2+/Fe3+ and formed a compact Fe2+/Fe3+ chelate film that played the role of anticorrosion. Additionally, new water-based anticorrosion coating was prepared by applying a mixture of RC-GAE and other additives to form polymer composites on the rusty steel plates. Both adhesion test and neutral salt spray test indicated that the anticorrosion coating presented a good corrosion resistance and a remarkably strong film adhesion of the new water-based anticorrosion polymer composites coating.

Indium oxide (In2O3) hollow microspheres were prepared using yeast as a bio-template with the aid of a precipitation method. The yeast provided a solid frame for the deposition of In(OH)3 to form the precursor. The resulting In2O3 hollow microspheres were obtained by calcining the precursor at 650 °C. The samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2 adsorption–desorption isotherms and UV–Vis diffuse reflectance spectroscopy. The results showed that the diameter of the In2O3 hollow microspheres was about 2.0–3.0 μm and the spherical shells were composed of In2O3 nanoparticles with a size of ∼20 nm. The BET specific surface area of the sample was 19.23 m2 g−1. The photoelectrocatalytic test results showed that the photoelectrocatalytic degradation efficiency of methylene blue (MB) using In2O3 hollow microspheres as catalysts under visible light irradiation and a certain voltage could reach above 95% after 4 hours, much higher than that of only photodegradation. The enhanced photoelectrocatalytic activity could be attributed to the hydroxyl radicals HO˙ produced by the light irradiation reaction process which could oxidize the electron donors and were beneficial to reducing the recombination of electrons and holes.

Both porous and scale-like wall zirconia (ZrO2) hollow microspheres were successfully prepared through a facile and mild microwave solvothermal method using the rape pollen as biotemplates. The formation mechanisms were discussed for both ZrO2 hollow microspheres fabricated using pollen biotemplate with different pollen treatments. The porous ZrO2 hollow microspheres had a specific surface area of 40.92 m2·g–1, significantly higher than scale-like wall ZrO2 hollow microspheres (24.79 m2·g–1) and ZrO2 particles (27.99 m2·g–1). The adsorption test results showed that porous ZrO2 hollow microspheres had a higher adsorption capability (96.98 g·mg–1) than scale-like wall ZrO2 hollow microspheres (38.55 g·mg–1) and ZrO2 particles (32.03 g·mg–1) for Congo red. The adsorption followed pseudo-second-order kinetics, and the adsorption process was homogeneous adsorption of monolayer.

A novel two-layer reinforced carbon fiber (CF), i.e., Ag nanoparticles (Ag NPs)/graphene oxide (GO) reinforced CF (named as CF/Ag/GO) was prepared by an electrochemical deposition and electrophoretic deposition (EPD) consequently. The modified fiber showed an increased interfacial shear strength (IFSS) and tensile strength. Transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectra (FTIR), X-ray photoelectron spectroscopy (XPS), Raman spectrometer, atomic force microscopic (AFM) and dynamic contact angle analysis (DCA) were carried out to investigate CF reinforced composites. And test results demonstrated that the presence of Ag NPs and GO sheets increased the surface roughness and surface energy of CFs significantly. IFSS of CF/epoxy and the tensile strength of CFs were increased by 86.1% and 36.8%, respectively. Ag NPs filled in the cracks in CF effectively to enhance the tensile strength, while GO sheets improved the wettability of resin on CFs and formed mechanical interlocking between CFs and epoxy resin. These Ag NPs and GO sheets worked together in a ferocious synergy on the interface of CF and epoxy to cause the enhanced mechanical properties.

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

Blends of compatibilized polyoxymethylene (POM)/ethylene butylacrylate copolymer (EBA)/ethylene-methyl acrylate-glycidyl methacrylate copolymer (EMA-GMA) and uncompatibilized POM/EBA were investigated. The notched impact strength of the compatibilized blends was higher than that of their uncompatibilized counterparts. The toughness of the POM blends was improved obviously with relatively low loading of EBA. Fourier transform infrared spectroscopy (FTIR) spectra of EMA-GMA, pure POM, and POM/EBA/EMA-GMA blends indicated that epoxy groups of EMA-GMA reacted with terminal hydroxyl groups of POM molecular chains. The glass-transition temperature (Tg) values of the POM matrix and the EBA phase were observed shifted to each other in the presence of EMA-GMA compatibilizer indicating that the compatibilized blends had better compatibility than their uncompatibilized counterparts. With the addition of EBA to POM, both the compatibilized and uncompatibilized blends showed higher onset degradation temperature (Td) than that of pure POM and the Td values of the compatibilized blends were higher than those of their uncompatibilized counterparts. The scanning electron microscopy showed better EBA particles distribution state in the compatibilized system than in the uncompatibilized one. The compatibilized blend with an obvious rougher impact fracture surface indicated the ductile fracture mode. POLYM. ENG. SCI., 2017. © 2017 Society of Plastics Engineers

The NiO/TiO2 p-n heterojunction composites were synthesized by electroless plating and annealing, which resulted in TiO2 nanotube arrays coated with a layer of NiO particles. The morphology, composition, and structure of NiO/TiO2 p-n heterojunction composites were corroborated by scanning electron microscopy, X-ray diffraction, FT-IR spectra, X-ray photoelectron spectroscopy, and UV–vis diffuse reflectance spectroscopy. The influences of electroless plating time and annealing temperature on the photoelectrochemical performance of the composites were investigated, and their photocathodic protection performance for 304SS under visible light irradiation were also evaluated in 3.5% NaCl solution through open-circuit potential, photoresponse spectra, and Tafel polarization curves. NiO/TiO2 heterojunction composites prepared under optimum conditions induce considerable enhancement of light absorption and exhibit excellent photoelectrochemical performance, which provide better photocathodic protection for 304SS.

Common organic coatings are hardly conductive and seldom applied in electromagnetic shielding fields. Thereby, the thermoplastic conductive nanocomposites, waterborne silicon-acrylic emulsion (SAE) merged with multi-walled carbon nanotubes (MWCNTs) and silica sols (Si), were prepared via co-blending method. Compared with neat SAE, the conductivity of composite latex (5 wt.% MWCNT and 1.5 wt.% Si) was raised nearly seven orders of magnitude, and the tensile strength and Young’s modulus were enhanced to 366% and 177%, respectively. The contact angle was raised from 59° to 84°. The curing temperature was decreased by 12.8 °C. These enhancements proved that the addition of MWCNTs and silica sol could boost the electrical, mechanical, curing, heatproof and waterproof performances of SAE, which will be employed in high-property conductive paint areas, including the flexible and stretchable devices.

With the rapid development of industry and agriculture and the greatly improved living conditions, the resultant gradually deteriorated environments threaten the human beings. Refractory or even toxic pollutants, which are from different industries such as printing and dyeing, pesticides, chemicals, petrochemicals, plastics and rubber, seriously threat the ecosystems and human health. Having the advantages of flexible composition, unique structure, high stability, memory effect, easy preparation and low cost, hydrotalcite compounds have a great potential in sewage degradation and environmental protection. This study focuses on the adsorption and catalytic properties (such as photocatalysis, electrocatalysis and photoelectrocatalysis) of hydrotalcite-derived materials for treating organic, inorganic and heavy metal ion sewage. The types of adsorption and catalysis, and the effects of various influencing factors on the degradation efficiency were discussed as well.

Thermoplastic conductive composites, namely, soap-free styrene–acrylic emulsion (S-A)/carbon nanotubes (CNTs) modified with carboxyl (–COOH) groups, were successfully synthesized by an in-situ semi-continuous seed emulsion pre-emulsification polymerization with allyloxy decyl polyoxyethylene ether (10) (KL) as a reactive emulsifier. The fracture surface scanning electron microscopy (SEM) images of the films illustrated that CNTs are inlayed in the S-A matrix and shaped into a conductive network for electron transport. Compared with neat S-A, the performance of the composites was greatly improved. The curing temperature of the composite emulsion with 4 wt% CNT–COOH was dropped by 16.4 °C. The electrical conductivity of the latex film was improved by eight orders of magnitude. The tensile strength and Young's modulus of the film were boosted by 483% and 2475%, respectively. Additionally, water resistance was ameliorated. These enhancements confirmed that the addition of CNTs can strengthen the curing, heatproof, mechanical, electrical, and waterproof properties of the S-A, which provides a new strategy for the modification of waterborne emulsion.

The composite TiO2 nanotube arrays/5,10,15,20-tetrakis(4-chlorophenyl) porphyrin (H2TClPP-TNTs) photoelectrode with high visible light photoelectrochemical properties was prepared by a facile surface adsorption method. The morphology, composition and optical property of H2TClPP-TNTs photoelectrode was investigated by scanning electron microscopy, X-ray diffraction, FT-IR spectra, X-ray photoelectron spectroscopy and UV–vis diffuse reflectance spectroscopy. The sensitization of H2TClPP on TNTs significantly extended the visible light response, the as-prepared H2TClPP-TNTs photoelectrode exhibits excellent photoelectrochemical performance and photocatalytic activity. The photodegradation efficiency of rhodamine B by using H2TClPP-TNTs irradiated under visible light for 4 h was up to 92.8%, which was higher than that of pure TiO2 nanotube arrays.

ZrO 2 particles with different microstructure have been fabricated through an easy method with chitosan of different molecular weights as template. The chitosan of different molecular weights was obtained through synergistic degradation of raw chitosan by α-amylase and H 2 O 2 using microwave hydrothermal method in low concentration acetic acid (1% V / V ). The as-synthesized ZrO 2 particles were characterized by wide-angle powder X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and N 2 adsorption⿿desorption. The possible formation mechanism of ZrO 2 particles with different microstructure has been proposed, and the photocatalytic activity of the as-synthesized products was assessed by monitoring the photodegradation of Rhodamine B (Rh B) under UV irradiation. Morphologies of as-synthesized ZrO 2 particles changed significantly with the different molecular weight of chitosan. As the molecular weight of chitosan decreased, the morphologies of as-synthesized ZrO 2 particles showed aggregate, nano-cubes, and nano-sheets, respectively. The ZrO 2 particles prepared with lower molecular weight chitosan as the template showed higher photocatalytic activity. The degradation efficiency of ZrO 2 with 3.1 y 10 7 and 2.4 y 10 4 Da chitosan as template was 64.4% and 86.2%, respectively.

Stabilized spherical hollow zirconia was fabricated using calcium carbonate as template through a simple precipitation method. The as-prepared products were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM) and nitrogen adsorption–desorption isotherms (BET). Adsorption performance of the as-prepared products toward Congo red (CR) aqueous solutions was tested and discussed. Results show that the prepared hollow ZrO2 microspheres after calcination displayed tetragonal crystalline reflection peaks and copied the morphology of CaCO3 template very well with a diameter of ∼ 1 μm, and the amount of zirconium n-Butoxide and reaction time play important roles in the formation of special morphology and structure. A possible formation mechanism was proposed according to the observed results. The as-prepared hollow ZrO2 microspheres after calcination exhibit much better adsorption performance for CR aqueous solutions compared with hollow ZrO2 microspheres before calcination and ZrO2 nanoparticles fabricated without template through the same method due to their crystalline structure and large specific surface area.

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 the γ-GPS coatings on CRI, this paper is the first to study the effect of metal ions added in the silane solutions on the anti-corrosion properties of the γ-GPS coatings, and it has been confirmed that the anti-corrosion properties changed when Zn2+ (or Mg2+) is present.

Novel waterborne acrylic resin modified by cellulose acetate butyrate was successfully synthesized by a homogeneous solution polymerization with 2-butoxy ethanol, cellulose acetate butyrate and acrylic monomers as raw materials, N, N - dimethyl ethanolamine as neutralization and γ-aminopropyltriethoxysilane (KH-550) as curing agent. The influences of the cellulose acetate butyrate and curing agent content on the properties of the waterborne acrylic resin were investigated. As a curing agent, KH-550 not only improved the cross-linking density of the resin effectively, but also bonded to the substrate to form a molecular layer of silane. Cellulose acetate butyrate and KH-550 were found to reduce the curing temperature of the resin. The tensile strength of the coating added with the curing agent (5.89 MPa) was significantly improved compared to that of cellulose acetate butyrate modified resin (1.49 MPa). This kind of environment-friendly waterborne acrylic resin has a strong potential application in wood coatings, automobile coatings and other fields.

Multi-walled carbon nanotubes (MWCNTs)/waterborne acrylic resin nanocomposite coatings were synthesized by a solution mixing method using 3-aminopropyltriethoxysilane (KH-550) coupling agent as the curing agent. The improvements on thermostability, conductibility, mechanical performances, and hydrophobicity of the as-prepared composite coatings were evaluated. The conductivity was improved by six orders of magnitude compared to pure waterborne acrylic resin. CNTs greatly enhanced the thermostability and reduced the curing temperature. The tensile test showed that the introduction of CNTs significantly enhanced the mechanical performances of the resin. The sample with 5 wt% CNTs exhibited the largest tensile strength, which was higher than pure resin. Moreover, the coating had an improved surface hydrophobicity. 6 wt% CNTs increased the contact angle of the coating from 81.32° to about 90°.

The CeO₂ nanoboxes with well-defined hollow structure were fabricated by template-engaged coordinating etching of Cu₂O cubes based on Pearson’s hard and soft acid-base principle. The morphologically uniform CeO₂ nanoboxes have an average edge length of 400 nm and shell thickness of around 60 nm. The strong chemical affinity between Cu+ and S₂O(2− 3) was the driving force for the etching of Cu₂O templates and the formation of shells. A possible formation mechanism of CeO₂ nanoboxes was proposed. The synthesized CeO₂ nanoboxes exhibit good photocatalytic activity for photodegradation of acid orange 7 (AO 7) under visible light irradiation.

Zirconia hollow microboxes were prepared using calcium carbonate cubes as templates. The as-prepared products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen adsorption–desorption isotherms. Adsorption performance of the as-prepared products toward Congo red (CR) aqueous solutions was tested and discussed. Results show that ZrO2 hollow microboxes copied the morphology of the CaCO3 template very well with a diameter of ∼1.5 μm and a possible formation mechanism was proposed according to the observed results. The Langmuir surface area and BET specific surface area of ZrO2 hollow microboxes before calcination are 301.65 m2 g−1, 247.88 m2 g−1, respectively and the maximum adsorbance was found to be 188.02 mg g−1 which is much higher than that of ZrO2 hollow microboxes after calcination (90.86 mg g−1) and ZrO2 nanoparticles (57.86 mg g−1). The adsorption kinetics and isotherms can be well described by the pseudo-second order rate model and Langmuir equation, respectively. These results indicate that ZrO2 hollow microboxes before calcination have great potential in removing dyes from a water environment.

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.

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.

Indium oxide (In

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.

Porous copper oxide (CuO) hollow microspheres have been fabricated through a simple hydrothermal method using PS latex as templates. The as-obtained samples were characterized by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffractometry (XRD) and Fourier transform infrared spectroscopy (FTIR). The influences of the mole ratio of Ethylenediamine (C 2 H 8 N 2 ) and copper acetate (Cu(Ac) 2 ·H 2 O), hydrothermal temperature and time on the size and morphologies of the final products have been investigated. The possible formation mechanism of porous CuO hollow microspheres has been proposed and the specific surface area of the hollow microspheres with 81.71 m 2 /g is measured by BET method. The band gap value calculated from a UV–vis absorption spectrum of porous CuO hollow microspheres is 2.71 eV. The as-synthesized product exhibits high photocatalytic activity during the photodegradation of an organic dyestuff, rhodamine B (RhB), under UV-light illumination.

A simple hydrothermal process was adopted to self-assembly prepare high infrared reflective antimony trioxide with three-dimensional flower-like microstructures. The morphologies of antimony trioxide microstructures were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and high resolution transmission electron microscopy (HRTEM) respectively. It is also found that experimental parameters, such as NaOH concentration, surfactant concentration and volume ratio of ethanol–water played crucial roles in controlling the morphologies of Sb2O3 microstructures. A possible growth mechanism of flower-like Sb2O3 microstructure was proposed based on the experimental data. UV–vis–NIR spectra verified that the near infrared reflectivity of the obtained flower-like microstructures could averagely achieve as 92% with maximum reflectivity of 98%, obviously higher than that of other different morphologies of antimony trioxide microstructures. It is expected that the flower-like Sb2O3 nanostructures have some applications in optical materials and heat insulation coatings.

Hollow spindle-like and cobblestone-like Sb2O3 microstructures, have been successfully synthesized via a hydrothermal method by using cetyltrimethylammonium bromide (CTAB) as soft-templates. Results from XRD, SEM, TEM, Raman and BET showed that experimental parameters, such as the reaction temperature and time, played crucial roles in the respective morphological control of Sb2O3 microstructures. On the basis of these results, possible growth mechanisms for the formation of hollow spindle-like and cobblestone-like microstructures are presented and discussed.

Sb 2 O 3 nanowires with diameters of ∼233 nm and microspheres assembled by these nanowires were successfully synthesized by a simple poly-(vinylpyrrolidone) (PVP) assisted hydrothermal method. The morphologies, nano/microstructures and optical properties of the as-grown nanowires and microspheres were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV–vis diffuse reflection spectrum. It has been found that the experimental parameters, such as mineralizers, played crucial roles in the morphological control of Sb 2 O 3 nanowires. The possible growth mechanism of microspheres has been proposed.

The bow-tie-like antimony trioxide (Sb 2 O 3 ) nanostructures are composed of sheet-like morphology. Each Sb 2 O 3 nanosheet is a single crystal with the [0 0 1] growth crystallographic direction, which has a width of ∼400 nm over its entire length, a length of up to ∼2 μm, and a thickness of ∼50 nm. The influences of several experimental parameters on the morphology of nanostructures have been investigated in detail. On the basis of the time-dependent experimental results, a possible formation mechanism has been proposed. It is expected that the bow-tie-shaped Sb 2 O 3 nanostructures have some applications in optoelectronic devices.