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1.
纳米ZnO的许多优异性能使其成为人们研究的热点并得到广泛应用.ZnO是一种同时具有半导体和压电双重特性的材料.运用不同的工艺,目前已生长出纳米线(棒)、纳米带、纳米环、四角形纳米结构、纳米笼、纳米螺旋等多种特殊形态的纳米ZnO.由这些许多独特的形态,可以看出纳米ZnO是纳米材料家族中可以生长出的结构最多样的成员之一.这些纳米结构在光电、传导、传感以及生化等不同领域有很多潜在的新颖的应用前景.  相似文献   

2.
采用改进的微乳液法制备了Fe、Co掺杂ZnO纳米材料,并对制备材料的结构和形貌分别进行了X射线衍射(XRD)及扫描电子显微镜(SEM)表征。为了明确温度对ZnO纳米材料光学性质的影响,使用温控仪进行降温操作,对制备的ZnO及Fe、Co掺杂ZnO材料进行了光学性质的对比研究,得到变温条件下Zn0及Fe、Co掺杂ZnO纳米...  相似文献   

3.
氧化锌(ZnO)纳米结构的形态是已知纳米结构中最为多样的多功能材料之一,由于一维ZnO纳米结构在电子与光电子装置中如表面声波、光子晶体、光发射二极管、光电探测器、紫外激光器、生物/化学传感器、场效应晶体管等诸多领域均展现出其独特的物理化学性能,已经引起人们的极大研究热情.而选择不同元素掺杂为调节其电、光和磁性质提供了一种有效方法,对实际应用至关重要,因此一维纳米结构的掺杂日益成为研究和应用的焦点。按照掺杂方法和掺杂元素的不同,对目前ZnO一维纳米结构的掺杂进展进行了回顾,提出了掺杂工艺中存在的问题,并对其发展趋势及前景进行了展望。  相似文献   

4.
纳米氧化锌改性聚氨酯复合涂层的防腐性能   总被引:8,自引:0,他引:8  
研究了添加不同颜基比(P/B)ZnO的聚氨酯涂料在3.5%氯化钠溶液中的电化学阻抗谱特征,提出了涂层电极在浸泡阶段对应的不同阻抗模型,结果表明,添加量为P/B=0.3的纳米复合涂层,颜料分布均匀适中,具有最佳电化学及耐盐雾性能.纳米复合涂层的抗介质渗透能力明显优于普通涂层,其原因是纳米材料独特的表面效应使其致密性有所提高,  相似文献   

5.
功能纳米氧化物的结构和性能研究是无机功能材料研究领域的一个研究热点。一般认为纳米氧化物的性能主要由形貌,表面效应和颗粒尺寸效应所决定。目前已经有大量的文献报道介绍各种形状的纳米材料的合成,但材料的性能和大颗粒体相材料相比没有明显的差别。人们利用表面效应来研究纳米氧化物的化学活性及其在光催化环境净化和重金属离子吸附等方面的应用,或通过尺寸效应来解析纳米氧化物出现的奇特的光、电、磁等现象,但普遍忽略纳米材料发生性质改变的结构因素。事实上,纳米材料的性能是由其电子结构和表面吸附的水分子来决定的:电子结构完全依赖于材料的晶体结构和晶格尺寸,而表面吸附的水分子常常会导致光猝灭或发光性能变差的现象。我们对多种氧化物纳米材料进行系统研究,初步构筑了其结构-性能的关系。(1)纳米TiO_2表面吸附大量的水分子。高温脱水导致纳米颗粒度变大。金属纳米材料和金属氧化物材料的比热都大于大颗粒材料,文献都归结于尺寸效应。最新研究表面,扣除吸附水分子的贡献后,裸露的纳米材料TiO_2的比热在实验范围内和大颗粒的基本相同。(2)利用本征黄光作为探针研完了量子尺寸效应对高结晶度ZnO纳米棒的结构和能带结构的修饰。随着ZnO纳米棒直径的增加,...  相似文献   

6.
纳米ZnO材料的制备与应用研究进展   总被引:7,自引:0,他引:7  
李春明  刘会冲  徐华蕊 《材料导报》2003,17(5):39-41,78
纳米ZnO材料较普通ZnO材料,有着许多优异的性能和广泛的应用价值,对它的研究得到了高度的重视,而国内相对国外显得滞后。系统介绍了纳米ZnO粉体和薄膜的制备方法,认为水热法、sol—gel法、喷雾热分解法是纳米ZnO材料降低成本、产业化制备最有潜力的方法。而纳米ZnO材料将不仅可以在传统领域逐步替代普通ZnO材料,并五将在普通ZnO材料无法涉足的新型领域,如光电、敏感领域开拓出新的应用前景。  相似文献   

7.
纳米ZnO作为一种新型无机功能材料,有着许多优异的性能和广泛的应用。综述了纳米ZnO的不同制备方法及其特点,同时还阐述了其表面改性方法,并对ZnO纳米材料的发展前景进行了展望。  相似文献   

8.
在低温下制备了粒径小于10nm的ZnO纳米晶,用旋涂法制备ZnO纳米晶薄膜,XRD分析ZnO晶相是纤锌矿结构;SEM与AFM表明,纳米晶薄膜在300%退火后薄膜的厚度明显减小到130nm,表面粗糙度降低到3.27nm,粒径明显增大;紫外-可见吸收和透射比光谱表明,随着退火温度的增加,吸收边发生了红移,吸收肩更明显,薄膜具有高的透射率(75—85%);薄膜方阻随温度增加而增大,300℃以下退火方阻增加很小(小于8.5Ω/sq),400℃以上退火方阻大幅增加(大于21.1Ω/sq),因此,ZnO纳米晶薄膜最优退火温度点为300℃。  相似文献   

9.
在金属基板表面电沉积一层金属Zn纳米晶,将该纳米晶置于高温炉中,通过热氧化法成功制备了一维ZnO纳米针。研究了不同的热氧化温度因素对一维ZnO纳米针的制备及其形貌的影响。在本方法中,一维ZnO纳米针材料对应于初始电沉积层的Zn纳米晶颗粒,这与其他方法中ZnO的生长机制不同,可以认为本方法的ZnO的生长遵从自催化扩散机制。同时,研究了一维ZnO纳米针薄膜的场发射效应。  相似文献   

10.
采用热蒸发的方法在ZnO薄膜缓冲层上成功制备了高密度的ZnO纳米棒阵列,其中ZnO薄膜缓冲层是通过PLD(Pulsed Laser Deposition)的方法制得。与已有的报道不同,该方法未使用任何金属催化剂。X射线衍射仪(XRD)以及场发射扫描电子显微镜(FE-SEM)的结果表明,实验得到的ZnO纳米棒阵列整齐垂直排列在衬底上.此外,在常温下测量得到的光致发光(PL)谱和透射电子显微镜显示该ZnO纳米棒阵列结晶较好,无明显的缺陷,研究结果表明纳米棒阵列的形成主要归因于ZnO纳米棒和薄膜之间完美的晶格匹配。  相似文献   

11.
Zhang J  Liu X  Wang L  Yang T  Guo X  Wu S  Wang S  Zhang S 《Nanotechnology》2011,22(18):185501
α-Fe(2)O(3)@ZnO core-shell nanospindles were synthesized via a two-step hydrothermal approach, and characterized by means of SEM/TEM/XRD/XPS. The ZnO shell coated on the nanospindles has a thickness of 10-15 nm. Considering that both α-Fe(2)O(3) and ZnO are good sensing materials, we have investigated the gas sensing performances of the core-shell nanocomposite using ethanol as the main probe gas. It is interesting to find that the gas sensor properties of the core-shell nanospindles are significantly enhanced compared with pristine α-Fe(2)O(3). The enhanced sensor properties are attributed to the unique core-shell nanostructure. The detailed sensing mechanism is discussed with respect to the energy band structure and the electron depletion theory. The core-shell nanostructure reported in this work provides a new path to fabricate highly sensitive materials for gas sensing applications.  相似文献   

12.
Zinc oxide nanostructures: synthesis and properties   总被引:3,自引:0,他引:3  
This article provides a comprehensive review of the current research activities that focus on the ZnO nanostructure materials and their physical property characterizations. It begins with the synthetic methods that have been exploited to grow ZnO nanostructures. A range of remarkable characteristics are then presented, organized into sections describing the mechanical, electrical, optical, magnetic, and chemical sensing properties. These studies constitute the basis for developing versatile applications of ZnO nanostructures.  相似文献   

13.
ZnO nano-architectures were produced with the aid of a fast, simple and low cost microwave-assisted synthesis method. Solid semispherical ZnO nanoparticles on the order of 600 nm in diameter along with rice-like ZnO nanorods 95 nm thick were produced from butanol, triethanolamine (TEA), and zinc acetate dihydrate. Solid spherical ZnO nano-architectures with an average diameter of 250 nm were produced from the same starting materials in addition to NaOH. X-ray diffraction, scanning electron microscopy, and transmission electron microscopy were used to characterize the ZnO nano-architectures as well as the precursor. This method is cheap, fast and simple; capable of producing large quantities of each ZnO nanostructure. Investigation of the step-by-step formation mechanism for each ZnO nanostructure was conducted.  相似文献   

14.
在陶瓷衬底上制作叉指状金电极,采用低温水热法生长一维纳米结构氧化锌,制得氧化锌紫外光电导型探测器.探讨了反应溶液的浓度对氧化锌纳米结构形貌及紫外光电导特性的影响.X射线衍射分析表明,产物为六方纤锌矿结构的ZnO.扫描电镜观察显示.产物为一维纳米结构,因反应溶液浓度的不同直径介于80~500nm.光电测试表明,一维纳米结构氧化锌的紫外光电导特性受其表面形貌的影响显著.  相似文献   

15.
This review provides a background on the structure and properties of ZnO nanostructures. ZnO nanostructures are advantageous for many applications in sensing, photocatalysis, functional textiles, and cosmetic industries, which are described in this review. Previous work using UV Visible (UV–vis) spectroscopy and scanning electron microscopy (SEM) for ZnO nanorod growth analysis in-solution and on a substrate for determination of optical properties and morphology is discussed, as well as their results in determining the kinetics and growth mechanisms. From this literature review, it is understood that the synthesis process greatly affects nanostructures and properties; and hence, their applications. In addition, in this review, the mechanism of ZnO nanostructure growth is unveiled, and it is shown that by having greater control over their morphology and size through such mechanistic understanding, the above-mentioned applications can be affected. The contradictions and gaps in knowledge are summarized in order to highlight the variations in results, followed by suggestions for how to answer these gaps and future outlooks for ZnO nanostructure research.  相似文献   

16.
We present a two-step electrochemical deposition process to synthesize hierarchical zinc oxide (ZnO) nanorod-nanosheet structures on indium tin oxide (ITO) substrate, which involves electrodeposition of ZnO nanosheet arrays on the conductive glass substrate, followed by electrochemical growth of secondary ZnO nanorods on the backbone of the primary ZnO nanosheets. The formation mechanism of the hierarchical nanostructure is discussed. It is demonstrated that annealing treatment of the primary nanosheets synthesized by the first-step deposition process plays a key role in synthesizing the hierarchical nanostructure. Photovoltaic properties of dye-sensitized solar cells (DSSCs) based on hierarchical ZnO nanostructures are investigated. The hierarchical ZnO nanorod-nanosheet DSSC exhibits improved device performance compared to the DSSC constructed using photoelectrode of bare ZnO nanosheet arrays. The improvement can be attributed to the enhanced dye loading, which is caused by the enlargement of internal surface area within the nanostructure photoelectrode. Furthermore, we perform a parametric study to determine the optimum geometric dimensions of the hierarchical ZnO nanorod-nanosheet photoelectrode through adjusting the preparation conditions of the first- and second-step deposition process. By utilizing a hierarchical nanostructure photoelectrode with film thickness of about 7 μm, the DSSC with an open-circuit voltage of 0.74 V and an overall power conversion efficiency of 3.12% is successfully obtained.  相似文献   

17.
采用水热法在PS模板上制备了不同的ZnO纳米阵列,通过控制反应时间得到不同长径比的ZnO纳米阵列,真空场发射测试表明,使用PS模板的ZnO纳米阵列的场发射性能得到改善,主要因为长纳米棒与短纳米管交叉两层的阵列结构导致屏蔽效应减弱。较长反应时间制备的ZnO纳米棒具有较大的长径比,场发射较好。多次重复场发射测试发现,本实验制备的ZnO纳米棒阵列的场发射稳定性不是很好,还需进一步改善。  相似文献   

18.
The performance of photoelectrochemical cell (PEC) strongly depends on the physical properties of photovoltaic material. Polyvinylpyrrolidone (PVP), cetyltrimethylammonium bromide (CTAB) and hexamethylenetetramine (HMT) surfactants were used to modify the morphology nanostructure of ZnO films by a simple technique, namely, ammonia-assisted controlled hydrolysis technique during their growth process. The film treated with PVP, CTAB and HMT produce the nanostructure shape of nanoflower, nanowire and nanorod (NR), respectively. These ZnO samples were utilised as photovoltaic materials in a PEC of FTO (fluorine tin oxide)/ZnO/electrolyte/platinum. It was found that the photovoltaic parameters such as short-circuit current density (Jsc), open-circuit voltage (Voc) and fill factor (FF) are influenced by the morphology in term of shape and particle size and optical property of the ZnO NR. The PEC utilising the ZnO sample treated with HMT surfactant demonstrated the highest Jsc of 0.47 mAcm?2, Voc of 0.46 V, FF of 29.2% and η of 0.06%, respectively, since it possesses the lowest energy gap.  相似文献   

19.
Zinc (Zn) thin films were prepared by direct current magnetron sputtering as precursors with different deposition times. Zinc oxide (ZnO) nanostructures such as nanowires, nanobelts and nanoblades were then synthesized from the Zn precursors by wet-oxidation process. The microstructures of the Zn precursor and ZnO nanostructures have been studied by scanning electronic microscopy and X-ray diffractometry. The optoelectronic properties were analyzed by photoluminescence measurement. It was found that the Zn precursor film with a porous top layer consisting of well-crystallized Zn grains is an essential for formation of ZnO nanowires. Along with time dependence study and temperature dependence studies, the ZnO nanostructure growth mechanisms during the wet-oxidation process are proposed: water vapor has a major influence on the initial stage, and the final dimensions of the nanostructure are controlled by the vapor-solid process.  相似文献   

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