In order to provide ultraviolet barrier, antifungal and antibacterial properties, nano-zinc oxide (ZnO) was added to lamellar zirconium phosphate (ZrP). The phosphate was synthesized via reaction of zirconium oxychlor...In order to provide ultraviolet barrier, antifungal and antibacterial properties, nano-zinc oxide (ZnO) was added to lamellar zirconium phosphate (ZrP). The phosphate was synthesized via reaction of zirconium oxychloride octahydrate and phosphoric acid following its chemical modification with Jeffamine and nano-ZnO. Diffractometric, morphological, thermal, structural and relaxometric evaluations were conducted. Fourier transform infrared spectroscopy (FTIR) revealed increase of the area between 4000 - 3000 cm<sup>-1</sup> due to the formation of ionic specie PO? <sup>+</sup>NH<sub>3</sub>-[C-(H)(CH<sub>3</sub>)-CH<sub>2</sub>-O-(C-(H)(CH<sub>3</sub>)-CH<sub>2</sub>-O)<sub>8</sub>-(CH<sub>2</sub>-CH<sub>2</sub>-O-CH<sub>3</sub>)] and nano-ZnO particles. Wide-angle X-ray diffraction indicated that intercalation of Jeffamine was successful. Thermogravimetry confirmed that nano-ZnO particle forced the expulsion of Jeffamine outside ZrP galleries. Scanning electron microscopy evidenced the Jeffamine intercalation and sample heterogeneity. Hydrogen molecular relaxation indicated the increase of molecular rigidity owing to the formation of ionic specie and the addition of nano-ZnO particles. It was postulated that a multifunctional and miscellaneous material constituted by as prepared ZrP, some delaminated ZrP platelets and nano-ZnO particles was achieved. The material has potential for usage as filler in polymeric composites.展开更多
Increasing need for materials with special features have brought various new inventions,one of the most promising hope for new material with special features and functionalities is composites materials.Thus,this study...Increasing need for materials with special features have brought various new inventions,one of the most promising hope for new material with special features and functionalities is composites materials.Thus,this study report an integration of zinc nanoparticles into kenaf/polyester polymer composite to introduce new behavior to the composite.The composite behaviors were compared for mechanical,thermal,moisture absorption and biodegradability properties.Prepared Zinc Oxide nanoparticles entrenched in the kenaf/polyestaer composites net structure through chemical bonds between kenaf/ZnO/polyester resin,existence of ZnO significantly influence the mechanical and thermals properties of composites.Thermal analysis based on(TGA)response revealed the integration of ZnO nanoparticles improved the thermal stability when thermal decomposition temperature beyond 3650 C.The thermal cracking decreased with present of ZnO and increase with kenaf content(layers).The modulus,Tensile strength,break at elongation,flexural modulus,flexural strength and impact strength of the composites with higher content kenaf/ZnO nanoparticle are 560 MPa,58MPa,1.8%,1300 PMa,68 MPa and 31 MPa,respectively.Thus,addition of kenaf layers and ZnO results in larger mechanical properties enhancement,the results of the contact angle show improvement in wetting of the fibres with addition of ZnO nanoparticles.展开更多
Zinc oxide (ZnO) and niobium oxide (NbOx) with a nano-island structure were deposited by a sputtering method on Al-coated glass substrates. Cells with a (ZnO or NbOx)/Al/glass|KNO3aq.|Al/ glass structure were assemble...Zinc oxide (ZnO) and niobium oxide (NbOx) with a nano-island structure were deposited by a sputtering method on Al-coated glass substrates. Cells with a (ZnO or NbOx)/Al/glass|KNO3aq.|Al/ glass structure were assembled, and electrochemical and photoelectrochemical properties were evaluated. The ZnO and NbOx electrodes had higher electrode potentials than the counter Al/glass electrode, and electron flows from the counter electrode to the ZnO and NbOx electrodes through the external circuit were commonly confirmed. In the ZnO-based cell, only faint photocurrent generation was seen, where Zn and Al elution from the ZnO electrode was found. In the NbOxbased cell, however, stable generation of electricity was successfully achieved, and electrode corrosion was not recognized even in microscopic observations. A photoelectrochemical conversion model was proposed based on potential-pH diagrams. In the case of nano-island structures formed at shorter NbOx deposition time, it was concluded that the photoelectrochemical reactions, which were proceeded in the immediate vicinity of the boundary among nano-islands, substrate, and electrolyte solution, were predominant for the photoelectrochemical conversion, and in the case of film structures with longer deposition time, the predominant reactions took place at the film surface.展开更多
The influence of processing parameters is investigated on the structural characteristics of single and mixed oxides produced by spray pyrolysis technique. The films were synthesized by spraying precursor solutions thr...The influence of processing parameters is investigated on the structural characteristics of single and mixed oxides produced by spray pyrolysis technique. The films were synthesized by spraying precursor solutions through a noz-zle onto a heated alumina substrate. The precursor consisted separately of aqueous solutions of tin chloride for SnO2 and zinc chloride for ZnO for single oxide cases, and aqueous solutions of tin chloride and indium nitrate for SnO2 + In2O3 and zinc chloride and indium nitrate solutions for ZnO + In2O3 for mixed oxide cases. The substrate temperature was varied accordingly for each single and mixed case. The films produced were characterized by X-ray Photoelectron Spectroscopy and Scanning Electron Microscopy. The results indicate that a non-homogenous film is formed at low temperature for both single oxides considered. The temperature has significant effect on the composition of the synthesized films of both single oxides below 450℃. The results for mixed oxides show that the best homogeneous films are obtained for 80 wt% ZnO + 20 wt% In2O3, and 80 wt% SnO2 + 20 wt% In2O3.展开更多
Flower-like zinc oxalate with a mean diameter of 50 μm was synthesized via the reaction of zinc acetate and dimethyl oxalate in ether-water bilayer refluxing systems at low temperature.Flower-like zinc oxalate micros...Flower-like zinc oxalate with a mean diameter of 50 μm was synthesized via the reaction of zinc acetate and dimethyl oxalate in ether-water bilayer refluxing systems at low temperature.Flower-like zinc oxalate microspheres can be further transformed into the similar morphology to zinc oxide by the decomposition of zinc oxalate at 500℃.Scanning electron microscopy（SEM）,X-ray diffraction（XRD）,thermogravimetric analysisdifferential scanning calorimetric（TG-DSC）,energy dispersive X-ray spectrum（EDX） and Fourier transforminfrared spectroscopy（FT-IR） were used to characterize the structure features and chemical compositions of the as-synthesized products.The UV-Vis and photoluminescence spectrum of flower-like zinc oxide microspheres were studied.The experimental results showed that flower-like zinc oxalate microspheres may be self-assembled by the zinc oxalate flakes.The ether-water volume ratio of 4：1 and refluxing temperature of 40℃ were considered to favor the preparation of flower-like zinc oxalate microspheres.展开更多
Nano-ZnO particle （nZnOp） reinforced polyethylene glycol （PEG）/polyethylene terephthalate （PET） （nZnOp/PEG/PET） copolymeric composites with different mass fractions and molecular weights of PEG are synthesized...Nano-ZnO particle （nZnOp） reinforced polyethylene glycol （PEG）/polyethylene terephthalate （PET） （nZnOp/PEG/PET） copolymeric composites with different mass fractions and molecular weights of PEG are synthesized via in-situ polymerization. The dispersion of nZnOp in copolymer matrixes and the effects of PEG and nZnOp particles on the crystallization behavior of the composites are studied by TEM, differential scanning calorimetry（DSC）, XRD and Fourier thansform infrared spectroscopy （FTIR ）. The results reveal that nZnOp particles are dispersed in the matrixes with nano-scale, and the addition of PEG induces more homogeneous dispersion of nZnOp. Simultaneously, these nanoparticles become nucleating centers during the crystallization of the matrixes. PEG segments can improve the flexibility of the PET molecular chain, resulting in the drop of the cold crystallization temperature and the rise of the crystallization rate of the composites. Furthermore, PEG （4 000） with the mass fraction of 10% can promote the crystallization rate of the composites. The mechanical properties show that the nano-particles strengthen and toughen the PET matrix, whereas PEG weakens these improve- ments.展开更多
Nowadays, fabrication of micro/nano-scale electronic devices with bottom-up approach is paid much research attention. Here, we provide a novel micro/nano-assembling method, which is accurate and efficient, especially ...Nowadays, fabrication of micro/nano-scale electronic devices with bottom-up approach is paid much research attention. Here, we provide a novel micro/nano-assembling method, which is accurate and efficient, especially suitable for the fabrication of micro/nano-scale electronic devices. Using this method, a self-powered ZnO/Sb-doped ZnO nanowire p–n homojunction ultraviolet detector(UVD) was fabricated, and the detailed photoelectric properties were tested. At a reverse bias of -0.1 V under UV light illumination, the photoresponse sensitivity of the UVD was 26.5 and the rise/decay time of the UVD was as short as 30 ms. The micro/nano-assembling method has wide potential applications in the fabrication of specific micro/nano-scale electronic devices.展开更多
文摘In order to provide ultraviolet barrier, antifungal and antibacterial properties, nano-zinc oxide (ZnO) was added to lamellar zirconium phosphate (ZrP). The phosphate was synthesized via reaction of zirconium oxychloride octahydrate and phosphoric acid following its chemical modification with Jeffamine and nano-ZnO. Diffractometric, morphological, thermal, structural and relaxometric evaluations were conducted. Fourier transform infrared spectroscopy (FTIR) revealed increase of the area between 4000 - 3000 cm<sup>-1</sup> due to the formation of ionic specie PO? <sup>+</sup>NH<sub>3</sub>-[C-(H)(CH<sub>3</sub>)-CH<sub>2</sub>-O-(C-(H)(CH<sub>3</sub>)-CH<sub>2</sub>-O)<sub>8</sub>-(CH<sub>2</sub>-CH<sub>2</sub>-O-CH<sub>3</sub>)] and nano-ZnO particles. Wide-angle X-ray diffraction indicated that intercalation of Jeffamine was successful. Thermogravimetry confirmed that nano-ZnO particle forced the expulsion of Jeffamine outside ZrP galleries. Scanning electron microscopy evidenced the Jeffamine intercalation and sample heterogeneity. Hydrogen molecular relaxation indicated the increase of molecular rigidity owing to the formation of ionic specie and the addition of nano-ZnO particles. It was postulated that a multifunctional and miscellaneous material constituted by as prepared ZrP, some delaminated ZrP platelets and nano-ZnO particles was achieved. The material has potential for usage as filler in polymeric composites.
文摘Increasing need for materials with special features have brought various new inventions,one of the most promising hope for new material with special features and functionalities is composites materials.Thus,this study report an integration of zinc nanoparticles into kenaf/polyester polymer composite to introduce new behavior to the composite.The composite behaviors were compared for mechanical,thermal,moisture absorption and biodegradability properties.Prepared Zinc Oxide nanoparticles entrenched in the kenaf/polyestaer composites net structure through chemical bonds between kenaf/ZnO/polyester resin,existence of ZnO significantly influence the mechanical and thermals properties of composites.Thermal analysis based on(TGA)response revealed the integration of ZnO nanoparticles improved the thermal stability when thermal decomposition temperature beyond 3650 C.The thermal cracking decreased with present of ZnO and increase with kenaf content(layers).The modulus,Tensile strength,break at elongation,flexural modulus,flexural strength and impact strength of the composites with higher content kenaf/ZnO nanoparticle are 560 MPa,58MPa,1.8%,1300 PMa,68 MPa and 31 MPa,respectively.Thus,addition of kenaf layers and ZnO results in larger mechanical properties enhancement,the results of the contact angle show improvement in wetting of the fibres with addition of ZnO nanoparticles.
文摘Zinc oxide (ZnO) and niobium oxide (NbOx) with a nano-island structure were deposited by a sputtering method on Al-coated glass substrates. Cells with a (ZnO or NbOx)/Al/glass|KNO3aq.|Al/ glass structure were assembled, and electrochemical and photoelectrochemical properties were evaluated. The ZnO and NbOx electrodes had higher electrode potentials than the counter Al/glass electrode, and electron flows from the counter electrode to the ZnO and NbOx electrodes through the external circuit were commonly confirmed. In the ZnO-based cell, only faint photocurrent generation was seen, where Zn and Al elution from the ZnO electrode was found. In the NbOxbased cell, however, stable generation of electricity was successfully achieved, and electrode corrosion was not recognized even in microscopic observations. A photoelectrochemical conversion model was proposed based on potential-pH diagrams. In the case of nano-island structures formed at shorter NbOx deposition time, it was concluded that the photoelectrochemical reactions, which were proceeded in the immediate vicinity of the boundary among nano-islands, substrate, and electrolyte solution, were predominant for the photoelectrochemical conversion, and in the case of film structures with longer deposition time, the predominant reactions took place at the film surface.
文摘The influence of processing parameters is investigated on the structural characteristics of single and mixed oxides produced by spray pyrolysis technique. The films were synthesized by spraying precursor solutions through a noz-zle onto a heated alumina substrate. The precursor consisted separately of aqueous solutions of tin chloride for SnO2 and zinc chloride for ZnO for single oxide cases, and aqueous solutions of tin chloride and indium nitrate for SnO2 + In2O3 and zinc chloride and indium nitrate solutions for ZnO + In2O3 for mixed oxide cases. The substrate temperature was varied accordingly for each single and mixed case. The films produced were characterized by X-ray Photoelectron Spectroscopy and Scanning Electron Microscopy. The results indicate that a non-homogenous film is formed at low temperature for both single oxides considered. The temperature has significant effect on the composition of the synthesized films of both single oxides below 450℃. The results for mixed oxides show that the best homogeneous films are obtained for 80 wt% ZnO + 20 wt% In2O3, and 80 wt% SnO2 + 20 wt% In2O3.
基金supported by the National Natural Science Fundation of China (No. 20773109)the Natural Science Foundation of Jiangsu Educational Committee of China (No. 08KJB150005)
文摘Flower-like zinc oxalate with a mean diameter of 50 μm was synthesized via the reaction of zinc acetate and dimethyl oxalate in ether-water bilayer refluxing systems at low temperature.Flower-like zinc oxalate microspheres can be further transformed into the similar morphology to zinc oxide by the decomposition of zinc oxalate at 500℃.Scanning electron microscopy（SEM）,X-ray diffraction（XRD）,thermogravimetric analysisdifferential scanning calorimetric（TG-DSC）,energy dispersive X-ray spectrum（EDX） and Fourier transforminfrared spectroscopy（FT-IR） were used to characterize the structure features and chemical compositions of the as-synthesized products.The UV-Vis and photoluminescence spectrum of flower-like zinc oxide microspheres were studied.The experimental results showed that flower-like zinc oxalate microspheres may be self-assembled by the zinc oxalate flakes.The ether-water volume ratio of 4：1 and refluxing temperature of 40℃ were considered to favor the preparation of flower-like zinc oxalate microspheres.
基金Supported by the Program of Jiangsu Development & Reform Commission(2005)the Industrial-ization Boosting Program of College Scientific Reserach Achievements of the Education Department of Jiangsu Province(JHB06-03)~~
文摘Nano-ZnO particle （nZnOp） reinforced polyethylene glycol （PEG）/polyethylene terephthalate （PET） （nZnOp/PEG/PET） copolymeric composites with different mass fractions and molecular weights of PEG are synthesized via in-situ polymerization. The dispersion of nZnOp in copolymer matrixes and the effects of PEG and nZnOp particles on the crystallization behavior of the composites are studied by TEM, differential scanning calorimetry（DSC）, XRD and Fourier thansform infrared spectroscopy （FTIR ）. The results reveal that nZnOp particles are dispersed in the matrixes with nano-scale, and the addition of PEG induces more homogeneous dispersion of nZnOp. Simultaneously, these nanoparticles become nucleating centers during the crystallization of the matrixes. PEG segments can improve the flexibility of the PET molecular chain, resulting in the drop of the cold crystallization temperature and the rise of the crystallization rate of the composites. Furthermore, PEG （4 000） with the mass fraction of 10% can promote the crystallization rate of the composites. The mechanical properties show that the nano-particles strengthen and toughen the PET matrix, whereas PEG weakens these improve- ments.
基金supported by the National Natural Science Foundation of China (11374110, 51371085, 11304106)
文摘Nowadays, fabrication of micro/nano-scale electronic devices with bottom-up approach is paid much research attention. Here, we provide a novel micro/nano-assembling method, which is accurate and efficient, especially suitable for the fabrication of micro/nano-scale electronic devices. Using this method, a self-powered ZnO/Sb-doped ZnO nanowire p–n homojunction ultraviolet detector(UVD) was fabricated, and the detailed photoelectric properties were tested. At a reverse bias of -0.1 V under UV light illumination, the photoresponse sensitivity of the UVD was 26.5 and the rise/decay time of the UVD was as short as 30 ms. The micro/nano-assembling method has wide potential applications in the fabrication of specific micro/nano-scale electronic devices.
