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纳米ZnO/聚合物复合材料结合了纳米ZnO优异的物理化学性能和聚合物易加工、高强度的特点,可广泛应用在电子、环保、化工、生物工程等领域。乳液聚合法因工艺简单、安全,条件温和,成本低等优点被广泛用于制备纳米ZnO/聚合物复合材料。对乳液聚合法制备纳米ZnO/聚合物复合材料的研究现状进行了综述。首先阐述了制备纳米ZnO/聚合物复合材料的乳液聚合方法,并对各种方法进行比较;然后归纳了纳米ZnO/聚合物复合材料的形成机理,并对纳米ZnO/聚合物复合材料在光电、抗紫外与抗菌、涂料等方面的应用现状进行了总结;最后,提出了纳米ZnO/聚合物复合材料未来的发展方向。 相似文献
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采用自由基聚合制备了二烯丙基二甲基氯化铵(DMDAAC)-烯丙基缩水甘油醚(AGE)-甲基丙烯酸(MAA)共聚物(PDMDAAC-AGE-MAA),进而与纳米ZnO复合,制备了PDMDAAC-AGE-MAA/纳米ZnO复合材料。通过核磁共振氢谱与透射电镜分别对聚合物和复合材料进行表征;将复合材料应用于织物整理中,考察了整理后织物的抗菌性和紫外吸收等性能。核磁共振氢谱表明PDMDAAC-AGE-MAA共聚物成功制备;核磁共振氢谱表明PDMDAAC-AGE-MAA/纳米ZnO复合材料具有核壳结构;经复合材料整理后织物对大肠杆菌具有良好的抗菌性和吸收紫外性能。 相似文献
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采用均相沉淀法制备了氧化锌(ZnO)前驱体,通过煅烧前驱体制备了不同粒径的ZnO纳米颗粒,并在此基础上制备了ZnO/环氧纳米复合材料.借助TG、XRD和TEM等手段对纳米ZnO进行了表征,采用UV-VIS研究了ZnO含量、颗粒粒径等因素对复合材料光学性能的影响.研究结果表明:在紫外光区,提高ZnO的含量和选择ZnO最佳粒径,可以改善对紫外光的屏蔽效果;随着ZnO粒径的减小,ZnO对紫外光的屏蔽存在明显的蓝移现象,因此选择合适的粒径尤为重要.在可见光区,ZnO含量和颗粒粒径的影响相似,当ZnO含量低于0.07wt%、粒径小于27nm时复合材料的透过率几乎没有变化,增加含量或增大粒径透过率则随之下降.当ZnO的粒径为27nm时,添加0.07wt%的ZnO所制备的ZnO/环氧纳米复合材料具有优异的光学性能:在保持可见光区高透明性的同时又能够对紫外光区有良好的屏蔽效果,能够满足LED封装等光学器件的需要. 相似文献
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采用十八醇(OA)、硬脂酸(SA)、纳米氧化锌(纳米ZnO)、微米铜(Cu)、膨胀石墨(EG)按63.85∶36.15∶1.00∶1.00∶8.00质量配合比混合制得OA/SA/纳米ZnO/Cu/EG复合材料。采用扫描电子显微镜(SEM)、红外光谱(FT-IR)、差示扫描量热仪(DSC)、热重分析仪(TGA)及导热系数仪,表征其形貌、化学结构、热学性能和导热性能。结果表明,OA/SA/纳米ZnO/Cu/EG复合材料相变温度为55.38℃,相变潜热为195.4J/g,失重范围为213.27~359.05℃,失重率为91.8%,具有较好的热性能,经300次冷热循环后性能稳定。OA/SA/纳米ZnO/Cu/EG相变材料具有合适的相变温度,较高的潜热以及较低的成本,在储能系统尤其是保温容器中具有较大的应用潜力。 相似文献
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《功能材料》2021,(2)
通过溶胶凝胶法制备纳米氧化锌颗粒。利用XRD、红外光谱和SEM图谱对制备的纳米氧化锌的物相和形貌进行表征,在实验溶液中检测纳米氧化锌的溶解,通过SEM观察ZnO对污泥形态的影响,同时也研究ZnO对污泥硝化反应的影响。结果表明,实验制备的六方纤锌矿ZnO粉末纯净,结晶性良好,而且ZnO颗粒为纳米颗粒且分散性良好。在实验溶液中,随着纳米ZnO颗粒添加量增加,SBR溶液内的Zn~(2+)含量逐渐增加,反应时间为270 min时,添加10、20和60 mg/L纳米ZnO颗粒的SBR系统中Zn~(2+)含量分别为9.6×10~(-3)、16.3×10~(-3)、36.1×10~(-3)mg/L。通过SEM观察到纳米ZnO颗粒添加后,污泥表面发现明显的纳米颗粒团聚物,污泥表面存在许多粉末状物质,很难找到黏膜状的胞外聚合物。ZnO颗粒添加量为0 mg/L的时候,颗粒污泥对氨氮的去除率可以达到96.4%,当ZnO颗粒添加量增至10和60 mg/L时,颗粒污泥对氨氮的去除率降为82.1%和59.6%。 相似文献
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Shashi B. Rana Vimal K. Bhardwaj Satbir Singh Amarpal Singh Navneet Kaur 《Journal of Experimental Nanoscience》2014,9(9):877-891
In this study, a precipitation method was used to synthesise ZnO nanoparticles using suitable precursors. An efficient surface modification method was proposed in order to reduce the agglomeration among synthesised small sized ZnO nanoparticles using 2-aminothiophenol as a capping agent. This article briefly investigated the effects of capping agent like 2-aminothiophenol on the optoelectronic properties of ZnO nanoparticles. The modified effectivity of 2-aminothiophenol has been examined on the nanosized ZnO nanoparticle for fluorescence and UV–visible (UV–vis) studies. The mechanism was studied for ZnO nanoparticles light emitting capability under different conditions. By facilitating the capping of ZnO with 2-aminothiophenol, fluorescence emission of the surface defects vanishes and ultraviolet (UV) emission increases. Surface capping by 2-aminothiophenol effectively covers most of the surface defects of ZnO and results in quenching of the visible region. The UV–vis absorption spectra of modified ZnO nanoparticles has been influenced by modified ZnO nanoparticles as a result of surface modification; where marked blue shift in absorption edge results. By surface modification of ZnO nanoparticles, change in optoelectronics properties has opened the new scope and possibilities to explore and fine tune the optical character of the modified ZnO for various optoelectronics applications such as UV laser. 相似文献
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Single-step synthesis of MWCNT and ZnO nanocomposite was conducted by co-chemical vapor deposition method. Electron microscopic analysis revealed that the fabricated nanostructures consisted of MWCNTs with a diameter of 60-70 nm which were coated with ZnO nanoparticles with an average size of 20-30 nm. The growth of ZnO nanoparticles took place after the formation of MWCNTs. EDS and XRD analyses could confirm the high crystallinity of ZnO deposited on the MWCNT surface. In comparison with pristine MWCNTs and ZnO nanoparticles, the UV absorption of MWCNT/ZnO nanocomposite was changed through modification with ZnO nanoparticles. 相似文献
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Newaz Mohammed Bahadur Masahide Sato Fumio Kurayama 《Materials Research Bulletin》2010,45(10):1383-187
A novel and rapid microwave method was used to prepare TiO2 coated ZnO nanocomposite particles. The resulted particles were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HR-TEM) and X-ray photoelectron spectroscopy (XPS). Results show that ZnO nanoparticles were coated with 6-10 nm amorphous TiO2 layers. In addition, zeta potential analysis demonstrated the presence of TiO2 layer on the surface of ZnO nanoparticles. Photoluminescence (PL) spectroscopy and UV-visible spectroscopy were used to investigate the optical properties of the nanoparticles. Compared to uncoated ZnO nanoparticles, the TiO2 coated ZnO nanoparticles showed enhanced UV emission. The UV-visible diffuse reflectance study revealed the significant UV shielding characteristics of the nanocomposite particles. Moreover, amorphous TiO2 coating effectively reduced the photocatalytic activity of ZnO nanoparticles as evidenced by the photodegradation of Orange G with uncoated and TiO2 coated ZnO nanoparticles under UV radiation. 相似文献
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Rational design of hybrid nanostructures through attaching nanowires with nanoparticles is an effective route to enhance the existing functionalities or to explore new ones. We carry out a systematic investigation on the photoluminescence of ZnO nanowire-Au nanoparticle hybrid nanostructures synthesized by attaching Au nanoparticles onto ZnO nanowires. Citrate-stabilized 40?nm Au nanoparticles effectively quench the green emission and enhance the UV emission of the ZnO nanowires, which is consistent with the wavelength-dependent generation of surface plasmon. The UV/green emission intensity ratio could be reversibly and reproducibly tailored by attaching/detaching Au nanoparticles. This enhancement of UV emission diminishes if the Au nanoparticles are coated with a polymer layer. We also find that the orange-red emission of the ZnO nanowires is related to the excess oxygen on the ZnO surface, and it is also tunable via annealing and surface modifications. 相似文献
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D.M. Fernandes A.A. Winkler Hechenleitner S.M. Lima L.H.C. Andrade A.R.L. Caires E.A. Gómez Pineda 《Materials Chemistry and Physics》2011
ZnO nanoparticles with average diameter of 25 nm were synthesized by a modified sol–gel method and used in the preparation of (in wt.%) (100 − x) poly(vinyl alcohol) (PVA)/x ZnO nanocomposite films, with x = 0, 1, 2, 3, 4, and 5. The PVA/ZnO films were exposed to UV radiation for 96 h and their thermal, morphological, and spectroscopic properties were investigated. In inert atmosphere, the nanocomposite films showed lower thermal stability than the pure PVA film, and the calorimetric data suggest an interaction between PVA and ZnO in the nanocomposite films. Some crystalline phases could be seen in the films with ZnO, and a direct dependence on the ZnO concentration was also observed. The original structure of ZnO nanoparticles remained unaltered in the PVA matrix and they were uniformly distributed on the film surface. The roughness of the PVA film was not modified by the addition of ZnO; however, it increased after 96 h of UV irradiation, more significantly in the nanocomposite films. The films showed an absorption band centered at 370 nm and a broad emission band in the UV–vis region when excited at 325 nm. 相似文献
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Large-scale synthesis of hexagonal cone-shaped ZnO nanoparticles with a simple route and their application to photocatalytic degradation 总被引:1,自引:0,他引:1
Xiangling Ren 《Materials Research Bulletin》2007,42(5):807-813
We report the large-scale synthesis of hexagonal cone-shaped ZnO nanoparticles by the esterification between zinc acetate and alcohol. The morphology of the ZnO nanoparticles was investigated by transmission electron microscopy, selected area electron diffraction and scanning electron microscopy measurements. The synthesized ZnO nanoparticles are single-crystalline with hexagonal phase and show a strong UV emission at −378 nm due to the excellent crystallinity of particles. A possible formation mechanism of the hexagonal cone-shape structure is proposed. Furthermore, the as-prepared ZnO particles exhibit high photocatalytic activity for the photocatalytic degradation of Rhodamine B, indicating that the ZnO nanostructure is promising as a semiconductor photocatalyst. 相似文献
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In this study, we prepared ZnO nanorods by a sonochemical method using a zinc acetate dihydrate as a new precursor. Well-aligned high-quality ZnO nanorods were synthesized on FTO glass by the sonochemical decomposition of zinc acetate dihydrate using a ZnO thin-film as the catalytic layer. The ZnO thin-films were deposited on the FTO glass by a sputtering method. To investigate their catalytic effects on the ZnO nanorods, catalytic ZnO thin-films of 20 nm, 40 nm, and 60 nm thickness were prepared by adjusting the sputtering time. The ZnO nanorods grown on catalytic layers with different thicknesses were characterized by SEM, XRD, and PL. The ZnO nanorods grown on the catalytic layer of 40 nm thickness show the best crystal and spatial orientation and as a result display the best optical properties. It was found that a catalytic ZnO thin-film of 40 nm in thickness yields well-aligned high-quality ZnO nanorods, due to its small surface roughness and structural strain. 相似文献
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Renata Marczak Doris Segets Michael Voigt Wolfgang Peukert 《Advanced Powder Technology》2010,21(1):41-49
Crystalline ZnO quantum dots have been synthesized by hydrolysis of zinc acetate dihydrate with lithium hydroxide in ethanolic solution. By varying different parameters of the synthesis process, the size of the ZnO particles can be controlled. Detailed investigation of the ripening of the nanoparticles evidenced that despite of the well-known influence of ageing temperature and time, the presence of the reaction byproduct lithium acetate strongly affects the ripening behaviour. In particular, the particle size can be almost completely arrested by the removal of this byproduct via reversible flocculation of the ZnO nanoparticles using heptane as an antisolvent. A closer analysis of the repeated washing process shows an initial improvement of the colloidal stability of the ZnO nanoparticles during the first purification cycle as it mainly removes the lithium acetate from the suspension and not the stabilizing acetate groups directly bound to the particle surface. With further washing the remaining acetate ligands are unable to maintain the stabilization against agglomeration of the ZnO nanoparticles. Thus, there exists an optimum between purification progress and colloidal stability. These findings are also confirmed by calculations according to the DLVO theory, which show that there exists nearly no primary minimum of small ZnO nanoparticles below 5 nm in the presence of stabilizing acetate ions whereas the decrease in acetate ions bound to the particle surface leads to a more and more pronounced primary minimum. The present work is of particular significance for the preparation of purified colloidal ZnO nanoparticles for studies of their electrical and optical properties with respect to their wide range of potential applications. 相似文献
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A new and rapid method for silica coating of ZnO nanoparticles by the simple microwave irradiation technique is reported. Silica-coated ZnO nanoparticles were characterized by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), high-resolution transmission electron microscopy (HR-TEM), CHN elemental analysis and zeta potential measurements. The FT-IR spectra and XPS clearly confirmed the silica coating on ZnO nanoparticles. The results of XPS analysis showed that the elements in the coating at the surface of the ZnO nanoparticles were Zn, O and Si. HR-TEM micrographs revealed a continuous and uniform dense silica coating layer of about 3 nm in thickness on the surface of ZnO nanoparticles. In addition, the silica coating on the ZnO nanoparticles was confirmed by the agreement in the zeta potential of the silica-coated ZnO nanoparticles with that of SiO2. The results of the photocatalytic degradation of methylene blue (MB) in aqueous solution showed that silica coating effectively reduced the photocatalytic activity of ZnO nanoparticles. Silica-coated ZnO nanoparticles showed excellent UV shielding ability and visible light transparency. 相似文献
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Jamil K. Salem Talaat M. Hammad Roger R. Harrison 《Journal of Materials Science: Materials in Electronics》2013,24(5):1670-1676
Ni doped ZnO nanoparticles were synthesized by a simple chemical method at low temperature with Ni:Zn atomic ratio from 0 to 5 %. The synthesis process is based on the hydrolysis of zinc acetate dihydrate and nickel acetate tetrahydrate followed by heat treatment at 65 °C under refluxing using methanol as a solvent. X-ray diffraction analysis reveals that the Ni-doped ZnO crystallizes in a wurtzite structure with crystal size of 4–11 nm. These nanocrystals self-aggregated themselves into hollow spheres of size of 600–170 nm. High resolution transmission electron microscopy image shows that each sphere is made up of numerous nanoparticles of average diameter 4 nm. The XRD patterns, Scanning electron microscopy and transmission electron microscopy micrographs of doping of Ni in ZnO are confirmed the formation of micro-spheres. Furthermore, the UV–vis. spectra and photoluminescence spectra of the Ni-doped ZnO nanoparticles were also investigated. The band gap of the nanoparticles can be tuned in the range of 3.55–3.36 eV by the use of the dopants. The observed red shift in the band gap from UV–visible analysis and near band edge UV emission with Ni doping may be considered to be related to the incorporation of Ni ions into the Zn site of the ZnO lattice. 相似文献