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1.
徐德前  庄仕伟  马雪  徐佳新  张宝林 《发光学报》2018,39(10):1425-1430
为了探究生长温度对外延ZnO纳米结构的影响,得到ZnO纳米结构可控生长的生长温度条件。利用金属有机化学气相沉积(MOCVD)方法,设计并获得了不同生长温度的ZnO外延样品,并对所有样品进行了表面形貌、光学特性、电学特性表征和结晶质量表征。实验结果表明:600℃生长的ZnO纳米柱横向尺寸最小,为65 nm左右,其光学特性也相对较好,晶体衍射峰的半峰宽最小,为0.165°,晶粒尺寸最大,为47.6 nm;电学性质相对最优的为640℃生长的ZnO样品,霍尔迁移率高达23.5 cm2/(V·s)。通过结果分析发现,生长温度能影响外延ZnO的生长模式,从而影响ZnO的形貌、光学、电学和晶体质量等特性。  相似文献   

2.
刘益春  陈艳伟  申德振 《物理》2005,34(9):654-659
一维纳米结构因其优异的光、电特性,在纳米电子学,光电子学器件等方面有重要的应用价值而倍受关注.在一维半导体纳米材料中,ZnO因激子束缚能大(60meV),可在室温获得高效的紫外发光而成为近年来继GaN材料后的又一研究热点.外延生长一维纳米结构ZnO及其量子阱材料除因量子尺寸效应更适宜做室温紫外发光、激光材料与器件外,还因界面和量子限制效应而具有许多新奇的光、电、和力学特性,可应用于纳米光电子学器件,传感器及存储器件,纳米尺度共振隧道结型器件和场效应晶体管的研制和开发.文章着重介绍了目前ZnO一维纳米结构制备,一维ZnO纳米异质结构和一维ZnO/Zn1-xMgxO多量子阱结构的外延生长和研究进展.  相似文献   

3.
吴晓萍  刘金养  林丽梅  郑卫峰  瞿燕  赖发春 《物理学报》2015,64(20):207802-207802
利用化学气相沉积法, 在铜箔上成功制备出形似自然界中刺球花的ZnO纳米花结构. 实验进一步研究了氧气和氩气流量比例分别为1:150, 1:200, 1:250和1:400时对ZnO纳米花结构和性能的影响. 结果表明, ZnO纳米花上的ZnO纳米棒的长径比随氧气氛的减少而减小; 在氧气和氩气流量比例为1:250时制备出的ZnO纳米花尺寸均匀、形貌均一、花型结构最完美. ZnO 纳米花的室温光致发光谱表明, 随着氧气氛的减少, 可见区域的发光从一个波包变成一个宽峰, 且与锌空位相关的缺陷发光峰在减弱, 与氧空位相关的缺陷发光峰在增强. 基于实验结果, 提出了一种在铜箔上制备ZnO纳米花结构的生长模型.  相似文献   

4.
简单溶液法制备氧化锌纳米棒及光学性质   总被引:1,自引:0,他引:1       下载免费PDF全文
以水合醋酸锌(ZnAc2·2H2O)和水合肼(N2H4·H2O)为反应物,在未使用任何表面活性剂的简单反应体系中制得了ZnO纳米棒。采用X射线衍射(XRD)、扫描电子显微镜(SEM)、高分辨透射电镜(HRTEM)和室温荧光光谱对产物的晶体结构、形貌和发光性质进行了表征和分析。测试结果表明,所得产物为六方纤锌矿结构ZnO纳米棒,平均直径为120 nm,产物结晶完整,尺寸均匀。这种简单溶液法制备的ZnO纳米棒在386 nm处具有一个尖锐的紫外发光峰,发射光谱的半峰全宽仅为18 nm,在可见光区有一个较弱的宽频发光带。在该反应体系中通过调控混合溶剂的配比,不使用任何表面活性剂的条件下,为ZnO一维纳米棒的形核和生长提供了微型反应空间。  相似文献   

5.
用化学溶液法以醋酸锌和六亚甲基四胺为原料在玻璃衬底上生长出不同形貌的亚微米和微米ZnO棒。探讨了反应液的酸碱度和反应液浓度对生成的ZnO棒形貌的影响,并分析了其生长机制。通过控制一定的酸碱度和溶液浓度,可以得到规则的六角ZnO棒状阵列。这种规则的六角棒沿着[002]方向生长。测量了样品的XRD,扫描电镜像(SEM),并对其发光性能进行了测量分析。其中规则六角ZnO棒的光致发光光谱中有一很强的峰值650nm红色宽谱带和一峰值约387nm的激子发光峰。激子发光峰加宽,实际上是自由激子的发光峰(380nm)和Zni的发光峰(430nm)的叠加。而红色发光峰可能是Vo2+中的电子和价带中的空穴辐射复合所致。  相似文献   

6.
采用低温热蒸发法在铜箔衬底上制备了大量ZnO纳米带、空心微米球和“海胆”状球.采用XRD、激光拉曼光谱仪、SEM和荧光光谱仪分别对ZnO纳米结构的微结构、形貌和光致发光性质进行研究.分析表明,纳米带的宽度大约为500 nm且长度超过10μm,而空心微米球的直径为5~10μm;ZnO纳米结构的发光主要是较强的蓝绿缺陷态发光,以及弱的紫外带隙态发光.铜衬底上ZnO纳米结构的制备使得ZnO纳米结构和导电衬底之间具有良好黏着性和电接触性.  相似文献   

7.
赵婧  闫小琴  张跃 《光散射学报》2009,21(4):312-316
本文报道In掺杂ZnO纳米棒的成功制备和对其结构以及光荧光性能的详尽研究。在室温条件下ZnO的共振拉曼谱线容易受到很强的荧光干扰, 甚至导致共振拉曼谱线完全被湮没。微量In掺杂入ZnO纳米棒中, 调控紫外发光峰由378 nm(纯ZnO)红移至397 nm; 另外, 在制备过程中引入过量的氧, 在样品中产生大量缺陷, 降低了ZnO的紫外近带边发光峰强度。这两方面导致在室温下可清楚的观察到In掺杂ZnO纳米棒的6阶LO拉曼峰。  相似文献   

8.
无催化法制备ZnO纳米针的结构及光学特性   总被引:3,自引:3,他引:0       下载免费PDF全文
采用无催化脉冲激光沉积(PLD)方法,在InP(100)衬底上生长纳米ZnO针状结构。采用扫描电子显微镜(SEM)、X射线衍射(XRD)以及光致发光(PL)谱等对ZnO纳米针的形貌、晶体结构和光学特性表征。SEM图像观察到ZnO纳米针状结构具有一定的取向性。XRD测试在2θ=34.50°处观测到强烈的ZnO(002)衍射峰,证实ZnO纳米针具有较好的c轴择优取向。室温PL谱在379nm处观察到了较强的自由激子发射峰(半峰全宽为13.5nm),而微弱的深能级跃迁峰位于484nm,二者峰强比值为11∶1,表明生长的纳米ZnO结构具有较高的光学质量。  相似文献   

9.
纳米ZnO微晶的合成及其发光特性   总被引:3,自引:2,他引:1  
以醋酸锌和尿素为主要原料,利用沉淀—水热法一步合成了纳米ZnO微晶。用XRD,TEM,FTIR等测试技术及光致发光光谱(PL)对纳米ZnO微晶进行了表征,并对其发光特性进行了分析。研究表明:该合成方法操作简单,得到的纳米ZnO颗粒基本无团聚,结晶性较好,平均粒径约为17.2nm,并在500~750nm范围内出现宽的PL峰,呈现出纳米材料的发光特征。  相似文献   

10.
采用溶剂热法在相同条件下分别制备了纯ZnO和石墨烯-氧化锌纳米复合物,通过SEM、TEM、拉曼和红外光谱等手段,对纳米复合物样品进行了形貌和结构表征。实验结果显示ZnO纳米颗粒成功地分散在少层石墨烯上。通过对比纯ZnO与复合物的形貌和光致发光谱,发现在没有石墨烯时,ZnO能够择优取向生长成六方棱柱,紫外发光峰弱且宽;在有石墨烯时,ZnO聚集成表面不规则的球形颗粒,紫外发光峰强且窄。上述结果表明ZnO形貌的变化和石墨烯的等离子体效应共同影响了ZnO的紫外发光,但石墨烯的表面等离子体效应起主导作用。  相似文献   

11.
The growth of ZnO nanorod arrays via a template-free sol-gel process was investigated. The nanorod is single-crystalline wurtzite structure with [0 0 0 1] growth direction determined by the transmission electron microscope. The aligned ZnO arrays were obtained directly on the glass substrates by adjusting the temperatures and the withdrawal speeds, without seed-layer or template assistant. A thicker oriented ZnO nanorod arrays was obtained at proper experimental conditions by adding dip-coating layers. Room temperature photoluminescence spectrum exhibits an intensive UV emission with a weak broad green emission as well as a blue double-peak emission located at 451 and 468 nm, respectively. Further investigation results show that the difference in the alignment of nanorods ascribes to the different orientations of the nanoparticles-packed film formed prior to nanorods on the substrate. Well ordered ZnO nanorods are formed from this film with good c-axis orientation. Our study is expected to pave a way for direct growth of oriented nanorods by low-cost solution approaches.  相似文献   

12.
Well-aligned ZnO nanorod arrays have been successfully fabricated directly on anatase TiO2 nanoparticle films via low-temperature hydrothermal processes. The effects of the reactive time, temperature and reactant concentration on the growth of the as-prepared ZnO crystals are investigated in detail, and the possible mechanisms of crystal ZnO nanorod growth are also suggested. The results show that the low reactant concentration is in favor of the increase in the aspect ratio of crystal ZnO nanorods with weak orientation, while the long reactive time and high reactant concentration are useful to prepare well-aligned crystal ZnO nanorod arrays. Interestingly, the typically constructed composite films exhibit superhydrophilic characteristic without UV irradiation. Moreover, a strong near-ultraviolet PL band centering at about 385 nm and a weak green PL band centering at about 525 nm can appear at the room temperature.  相似文献   

13.
Highly ordered and stepped ZnO comb-like structures were fabricated using conventional thermal evaporation method. Zn powder covered by a layer of a mixture of ZnO and graphite was employed as the Zn source. The obtained ZnO comb-like structures are several tens of micrometers and some of them are even up to 100 μm. Both the widths of the belts and the lengths of the branches gradually decrease along the growth direction of ZnO comb-like structures. Under the most suitable condition, ZnO nanorods branches have uniform diameters and are evenly distributed on the belt-like stem. Possible growth process of ZnO comb-like structures was discussed. The effect of growth temperature on the morphology of the obtained products was also investigated. Room-temperature photoluminescence spectra from the ZnO comb-like structures and the nanorods film reveal weak UV emission and strong green emission.  相似文献   

14.
采用两步法,即先用磁控溅射在Si(100)表面生长一层ZnO籽晶层、再利用液相法制备空间取向高度一致的ZnO纳米棒阵列.用扫描电子显微镜、X射线衍射、高分辨透射电子显微镜和选区电子衍射对样品形貌和结构特征进行了表征.结果表明,ZnO纳米棒具有垂直于衬底沿c轴择优生长和空间取向高度一致的特性和比较大的长径比,X射线衍射的(XRD)(0002)峰半高宽只有0.06°,选区电子衍射也显示了优异的单晶特性.光致发光谱表明ZnO纳米棒具有非常强的紫外本征发光和非常弱的杂质或缺陷发光特性. 关键词: ZnO纳米棒阵列 ZnO籽晶层 两步法 液相生长  相似文献   

15.
In this study, the optical properties of S- and Sn-doped ZnO nanobelts, grown by thermal evaporation, were investigated. The sulfur and tin contents in the nanobelts were about 12% and 8% (atomic), respectively. The average widths of the S- and Sn-doped ZnO nanobelts were 73 and 121 nm, respectively. Room temperature photoluminescence (PL) spectroscopy exhibits significantly different optical properties for the two types of nanobelts. The PL result of the S-doped ZnO nanobelts shows the broad visible emission with no detectable ultraviolet (UV) peak, while the PL result of the Sn-doped sample shows two emission bands, one related to UV emission with a strong peak at 376 nm that is blue-shifted by 4 nm in comparison to pure ZnO nanobelts, and another related to green emission with a weak peak. A weak peak in the UV region at 383 nm appeared after annealing the S-doped ZnO nanobelts at 600 °C. Additionally, the annealed S-doped nanobelts show a stronger peak in the visible emission region in comparison to that observed prior to annealing. The Sn-doped ZnO nanobelts are also affected by annealing, as the UV emission peak is blue-shifted to 372 nm after annealing.  相似文献   

16.
水热法制备Co掺杂ZnO纳米棒及其光学性能   总被引:3,自引:2,他引:1  
采用水热法在石英衬底上以Zn(CH3COO)2.2H2O和Co(NO3)2.6H2O水溶液为源溶液,以C6H12N4(HMT)溶液作为催化剂,在较低温度下制备了Co掺杂的ZnO纳米棒。采用X射线衍射(XRD)和扫描电子显微镜(SEM)对所生长ZnO纳米棒的晶体结构和表面形貌进行了表征,考察了Co掺杂对ZnO纳米棒微观结构和对发光性能影响的机制。结果表明:Co掺杂的ZnO纳米棒呈六方纤锌矿结构,具有沿(002)面择优生长特性,Co掺杂使ZnO纳米棒的直径变细;同时室温光致发光(PL)谱检测显示Co掺杂ZnO纳米棒具有很强的近带边紫外发光峰,而与深能级相关的缺陷发光峰则很弱。本研究采用水热法在石英衬底上于较低温度下生长出了具有较高光学质量的Co掺杂ZnO纳米棒。  相似文献   

17.
Different morphologies of zinc oxide (ZnO) nanorods and nanotubes, which were grown under the same conditions but different dissolving processes, are prepared in our experiment through hydrothermal method. After the growth process, cooling down the reactor naturally or dissolving at a constant temperature of 40 °C, preferential dissolution will occur at different places on the tip of ZnO nanorods. During the dissolution process, different dissolution rates on the entire surface of nanorod will lead to different nanostructures. ZnO nanorods and nanotubes on Cu substrates display the same PL property with strong green emission but weak UV emission, while ZnO nanorods on Si substrates exhibits a relatively strong UV emission.  相似文献   

18.
High quality vertical-aligned ZnO nanorod arrays were synthesized by a simple vapor transport process on Si (111) substrate at a low temperature of 520 °C. Field-emission scanning electron microscopy (FESEM) showed the nanorods have a uniform length of about 1 μm with diameters of 40-120 nm. X-ray diffraction (XRD) analysis confirmed that the nanorods are c-axis orientated. Selected area electron diffraction (SAED) analysis demonstrated the individual nanorod is single crystal. Photoluminescence (PL) measurements were adopted to analyze the optical properties of the nanorods both a strong UV emission and a weak deep-level emission were observed. The optical properties of the samples were also tested after annealing in oxygen atmosphere under different temperatures, deep-level related emission was found disappeared at 600 °C. The dependence of the optical properties on the annealing temperatures was also discussed.  相似文献   

19.
In the present paper, well-dispersed ZnO nano-, submicro- and microrods with hexagonal structure were synthesized by a simple low temperature hydrothermal process from zinc nitrate hexahydrate without using any additional surfactant, organic solvent or catalytic agent. The phase and structural analysis were carried out by X-ray diffraction (XRD), the morphological analysis was carried out by field emission scanning electron microscopy (FESEM) and the optical property was characterized by room-temperature photoluminescence (PL) spectroscopy. The results revealed the high crystal quality of ZnO powder with hexagonal (wurtzite-type) crystal structure and the formation of well-dispersed ZnO nano-, submicro- and microrods with diameters of about 50, 200 and 500 nm, and lengths of 300 nm, 1 μm and 2 μm, respectively, on a large-scale just using the different temperatures. Room-temperature PL spectrum from the ZnO nanorods reveals a strong UV emission peak at about 360 nm and no green emission band at ∼530 nm. The strong UV photoluminescence indicates the good crystallization quality of the ZnO nanorods. Room-temperature PL spectra from the ZnO submicro- and microrods reveal a weak UV emission peak at ∼400 nm and a very strong visible green emission at 530 nm, that is ascribed to the transition between VoZni and valence band.  相似文献   

20.
纳米氧化锌的紫外自发辐射与受激辐射   总被引:1,自引:0,他引:1       下载免费PDF全文
纳米结构的氧化锌兼备了宽直接带隙(Eg=3.34eV)、强激子束缚能(60meV)的优良特性,同时又具备了纳米材料独特的微结构与光电功能,可望成为高效率紫外发光二极管以及低阈值紫外半导体激光器的良好材料。以我们的工作为基础,利用不同结构的ZnO作增益介质,概述了低维ZnO纳米材料中的自发辐射与受激辐射过程,观察到了放大的自发辐射(ASE)与受激振荡现象,并讨论了自发辐射、ASE及受激辐射的产生机制。  相似文献   

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