共查询到19条相似文献,搜索用时 218 毫秒
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以乙酸锌为前驱物,乙醇、正丙醇和正丁醇为溶剂,不加入表面活性剂,通过改变反应体系中醇水体积比、pH值、前驱物浓度,在反应温度80℃、反应时间30 min的条件下,制备得到不同尺寸和形貌的纳米氧化锌粒子.通过透射电子显微镜(TEM)、X射线衍射和紫外-可见吸收光谱等方法对纳米氧化锌进行了表征.结果表明:所合成的纳米氧化锌样品在350~365 nm范围内具有较为明显的吸收峰,减小醇水体积比、减弱溶剂极性、增加前驱物乙酸锌浓度,均可以导致纳米氧化锌粒子尺寸变大、团聚加重,前驱物溶液pH值的改变对纳米氧化锌的吸收峰影响不大. 相似文献
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染料敏化太阳能电池(DSC)由于其工艺简单、成本低廉、理论光电转换效率高,逐渐成为硅基太阳能电池的有力竞争者.DSC电池的光阳极主要起到对染料分子中激发出来的电子进行传导的作用,其光阳极薄膜大多数是由氧化物纳米晶制备的.氧化物纳米晶存在大量界面电阻,导致能量势垒,从而使染料分子中光生电子-空穴对不能有效分离,制约了DSC电池光电转换效率的提高.而高长径比的一维氧化物纳米光阳极薄膜有望降低界面电阻,促进电子-空穴对的有效分离,将是DSC电池光阳极材料开发的重要发展方向.详细论述了染料敏化太阳电池用一维纳米氧化物光阳极薄膜的研究进展. 相似文献
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氧化锌纳米棒形貌对ZnO/Cu2O异质结太阳能电池光伏性能的影响 总被引:1,自引:0,他引:1
采用电化学沉积法制备了ZnO纳米棒,首先讨论了电化学沉积参数对氧化锌(ZnO)纳米棒形貌的影响,并对不同长度ZnO纳米棒的光吸收和反射等性质进行了研究.实验发现沉积时间是影响纳米棒长度、直径的重要因素,ZnO纳米棒的微观形貌对其光学性质有重要影响.然后以氧化锌纳米棒为n型材料,以氧化亚铜为p型材料,通过电化学沉积法构筑了ZnO/Cu2O异质结太阳能电池,并测试了其光伏性能,研究表明增长纳米棒阵列的长度使得开路电压、短路电流密度及光电转换效率等性能得到提升.最后,综合分析了氧化锌纳米棒形貌与所组装电池的性能之间的关系,发现调控氧化锌纳米棒的形貌是提高ZnO/Cu2O异质结太阳能电池光伏性能的有效途径. 相似文献
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一维结构的纳米氧化锌具有独特的电子和光电性能,在众多领域有着广阔的应用前景,故而对其合成方法的研究十分重要.本文中以聚乙烯醇作为修饰剂,通过水热法在较低的反应温度下制备了一维氧化锌纳米棒.分别用透射电镜、选区电子衍射和X射线衍射对产物形貌与结构进行了表征.研究发现,以聚乙烯醇为助剂在120℃反应24h可制备出具有六方结构的氧化锌纳米棒,其直径为50~80nm、长度为1~2μm.实验表明,聚乙烯醇在一维结构合成过程中起到关键作用,以Zn(0H)2为水热反应前驱体可制备出品质较高的一维氧化锌纳米棒. 相似文献
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目的 研究以乙酸锌和氢氧化钠为原料,利用水热合成法制备纳米氧化锌的最佳工艺条件及抗菌性能。方法 以纳米氧化锌的粒径和形貌为评价指标,讨论合成条件对产物的影响;基于单因素设计响应面实验,以抑菌圈直径为响应值,分析抑菌效果较好的纳米氧化锌的制备条件。结果 在水热温度为111.14 ℃,反应时间为10 h,乙酸锌浓度为0.02 mol/L时制备的纳米氧化锌的抗菌效果最好,大肠杆菌的抑菌圈直径为(17.265±0.011)mm。结论 水热温度、水热时间和前驱体浓度会影响纳米氧化锌的粒径和形貌;水热温度和前驱体浓度是影响纳米氧化锌抑菌性的显著因素,水热时间是非显著因素。 相似文献
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A facile and rapid electrodeposition route was developed to controllably synthesize well-aligned ZnO nanorod arrays on diverse substrates, such as seed-layer pre-formed, pristine indium tin oxide (ITO) and Si, using Zn(NO3)2·6H2O and hexamethylenetetramine (HMT) as the precursors. X-ray diffraction (XRD) and transmission electron microscopy (TEM) results indicated that seed-layer pre-modified of ZnO nanorod arrays (ZNRs) possessed single crystalline, a wurtzite crystal structure with preferential growth orientation along [0001] direction. The ZNRs on pre-modified ZnO seed-layer (ZSL) had diameters of 30-50 nm, and aligned vertically to the substrates. ZNRs on ZSL/ITO substrate exhibited a high transmittance (above 80%) in visible wavelength range and the red-shift of band gap energy. An electrochemical reaction model was proposed to explain the growth process of ZnO nanorods. Importantly, the rapid synthesis of ZNRs provided the feasibility of preparation of SERS (surface enhanced Raman scattering) nanocomposite within shorter time by a subsequent electrochemical etching. 相似文献
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Hind Fadhil Oleiwi Azmi Zakaria Chi Chin Yap Sin Tee Tan Hock Beng Lee Chun Hui Tan Riski Titian Ginting Abdelelah Alshanableh Zainal Abidin Talib 《Journal of Materials Science: Materials in Electronics》2018,29(4):2601-2609
Incorporating cadmium sulfide quantum dots (CdS QDs) onto ZnO nanorod (ZNRs) has been investigated to be an efficient approach to enhance the photovoltaic performance of the inverted organic solar cell (IOSC) devices based on ZNRs/poly (3-hexylthiophene) (P3HT). To synthesize CdS/ZNRs, different durations of deposition per cycle from 1 to 9 min were used to deposit CdS via SILAR technique onto ZNRs surface grown via hydrothermal method at low temperature on FTO substrate. In typical procedures, P3HT as donor polymer were spun-coating onto CdS/ZNRs to fabricate IOSC devices, followed by Ag deposition as anode by magnetron sputtering technique. Incorporation of CdS QDs has modified the morphological, structural, and optical properties of ZNRs. Incorporation of CdS QDs onto ZNRs also led to higher open circuit voltage (Voc) and short circuit current density (Jsc) of optimum ZNRs/CdS QDs devices due to the increased interfacial area between ZNRs and P3HT for more efficient exciton dissociation, reduced interfacial charge carrier recombination as a result of lower number of oxygen defects which act as electron traps in ZnO and prolonged carrier recombination lifetime. Therefore, the ZNRs/CdS QDs/P3HT device exhibited threefold higher PCE (0.55%) at 5 min in comparison to pristine ZNR constructed device (0.16%). Overall, our study highlights the potential of ZNRs/CdS QDs to be excellent electron acceptors for high efficiency hybrid optoelectronic devices. 相似文献
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S.A. VanalakarR.C. Pawar M.P. SuryawanshiS.S. Mali D.S. DalaviA.V. Moholkar K.U. SimY.B. Kown J.H. KimP.S. Patil 《Materials Letters》2011,65(3):548-551
Cadmium sulfide nanoparticles (CNPs) sensitized zinc oxide nanorod arrays (ZNRs) were synthesized in the two step deposition process at relatively low temperature. The vertically aligned ZNRs were grown on the conducting glass substrates (FTO) using aqueous chemical method, followed by the deposition of CNPs at 70 °C using chemical bath deposition (CBD) technique. The samples were characterized by optical absorption, X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS) and photoluminescence spectroscopy (PL). Further, the photoelectrochemical (PEC) performance of ZNRs with and without CNPs sensitization was tested in Na2S-NaOH-S and Na2SO4 electrolyte, respectively. When the CNPs are coated on the ZNRs, the optical absorption is enhanced and band edge is shifted towards visible region (525 nm) as compared with ZNRs (375 nm). The sample sensitized with CNPs shows higher photoelectrochemical (PEC) performance with maximum short circuit current of (Isc) 2.60 mA/cm2. 相似文献
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Jogender Singh D. Poondi T. Dobbins M. Mastro Pietro 《Materials and Manufacturing Processes》2008,23(3):228-240
A novel laser-liquid-solid interaction (LLSI) technique has been developed that is highly flexible and allows engineering nanomaterials in form of particles, rods, and tubes from liquid precursors. Synthesis reaction takes place in a molecular level and reaction rate is controlled by laser energy input, precursor solution chemistry, and other processing parameters including interaction time, and thermal conductivity of solid that is spinning in the solution. By the proper selection of liquid precursor, mono-dispersed silver nanoparticles were produced with average particle size 7-10 nm. Alloy composed Ag and Ni were produced in the form of nanoparticles and nanotubes with an average diameter of 40 nm. HRTEM of nanorod exhibited that Ag acted as seed for the synthesis of immiscible of Ag-Ni alloy. Laser writing of silver exhibited 50% lower electrical resistivity and eliminated many intermediate steps involved as compared to conventional silver patterning process. 相似文献
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Yu Qiu Dechao Yang Jixue Lei Heqiu Zhang Jiuyu Ji Bing Yin Jiming Bian Yu Zhao Lizhong Hu 《Journal of Materials Science: Materials in Electronics》2014,25(6):2649-2656
A simple and effective method of synthesizing nanorods (NRs) and the ability to control the size and aspect ratio of them are crucial for fabricating nanodevices. In this paper, we present a systematic study of the growth of ZnO NRs on common paper substrates using a hydrothermal approach by adjusting the growth conditions. By a slight variation of the solution concentration and the growth time, significant changes in morphology and size (aspect ratio) of the obtained ZnO NRs have been controlled. Moreover, the piezoelectric power generation from ZnO-paper nanogenerators grown with different precursor concentration and growth time are also investigated. It is found that the morphology and aspect ratio of NRs have significant influence on the piezoelectric behavior. This type of flexible piezoelectric nanogenerator will have potential applications in implantable biosensors and wearable self-powered electronic devices. 相似文献
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Zhang SL Cho BH Lee DD Lim JO Huh JS 《Journal of nanoscience and nanotechnology》2012,12(2):1521-1525
Controlled synthesis of ZnO nanorods (ZNRDs), nanotubes (ZNTs) and nanorings (ZNRs) has been carried out by a two-step sonochemical/chemical process at room temperature without any catalyst, template or seed layer. The crystallinity, structure and morphology of ZNRDs, ZNRs and ZNTs were examined by X-ray diffraction (XRD) analysis, scanning electron micrographs (SEM), high resolution transmission electron microscope (HR-TEM) and selected area electron diffraction (SAED). The as-prepared ZnO nanostructures were single crystalline with hexagonal cross-section and uniform size. The effect of precursor concentration on the growth and that of the etching duration on the hollow formation were analyzed, and the obtained results revealed that the precursor concentration and etching time play an important role in determining final morphologies of the samples. By tuning the etching time, the precise size control of ZNTs and ZNRs was achieved. Possible formation mechanisms of these nanostructures are proposed based on the experimental results. 相似文献
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Light absorption efficiencies (defined as the ratio of the absorption cross section to the total extinction cross section
at each resonance wavelength) of gold nanodisk and nanorod were calculated based on quasi-static approximation. The absorption
efficiency solely depends on the frequency of surface plasmon resonance. With increasing resonance wavelength, the absorption
efficiencies change in the same fashion for both nanodisk and nanorod. However, the resonance absorption at short wavelength
is easy to be obtained by gold nanodisk, whereas the resonance absorption at longer wavelength is easy to be obtained by gold
nanorod. High absorption efficiency (>98%) can be obtained in the visible region by increasing the aspect ratio of gold nanodisk.
Although the longitudinal absorption efficiency of gold nanorod is relative lower by increasing the aspect ratio, the absorption
efficiency is also tunable in the near infrared region, which makes it potentially useful in silicon solar cells and vivo
applications.
Jian Zhu and Jian-Jun Li have contributed equally to this work. 相似文献
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Free-standing Cu nanorod arrays on Cu foil have been fabricated by a template-assisted method. Cu nanorods were potentiostatically deposited on mechanically polished Cu foil using anodized aluminum oxide templates as the deposition mask. Three electrolyte systems were compared, including two acid copper sulfate based solutions and one alkaline solution. The most uniform nanorods were achieved in the alkaline electrolyte. The weight gain per unit area after electrodeposition has been used as a direct measure of average length of deposited Cu nanorods. It was found that our control over the uniformity in nanorod length across the array is important in reaching the maximized aspect ratio without aggregation. Through controlling the weight change it was possible to control the aspect ratio of nanorods and to avoid aggregation of nanorods. Our capability to fabricate free-standing Cu nanorod arrays of uniform height with maximized aspect ratio on Cu foil is especially important in applying this nanostructured Cu as a current collector in Li ion batteries. 相似文献
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Peng S Tian L Liang J Mhaisalkar SG Ramakrishna S 《ACS applied materials & interfaces》2012,4(1):397-404
Polypyrrole(PPy) nanorod networks with a high electrical conductivity of 40 S cm(-1) have been obtained in a high yield by employing an ion association of heparin-methylene blue as a new morphology-directing agent. The polypyrrole nanorod networks are mixed with different content of carbon nanoparticles to make PPy nanorod networks/carbon nanoparticles(PPy/C) counter electrodes. It is found that the PPy/C composite with 10% carbon content shows a lower charge transfer resistance and better catalytic performance for the reduction of I(3)(-), compared with the pristine PPy and carbon electrodes. The better catalytic performance is attributed to the interaction of the superior electrocatalytic activity of the unique polypyrrole nanorod networks and the carbon nanoparticles, which can accelerate triiodide reduction and electron transfer in the electrode. Under standard AM 1.5 sunlight illumination, the dye-sensitized solar cell based on the PPy/C composite with 10% carbon content as the counter electrode demonstrates a high efficiency of 7.2%, which is much higher than that of pristine PPy and carbon electrode-based DSCs and comparable to that of the thermal decomposed Pt-based DSC. 相似文献